Quantum Optics Lab Seminar
What: we make reports on quantum optics
Where: room #128 A, Department of GeneralPhysics 1
and/or online in ZOOM
When: on Friday from 11:00 a.m. untill lunch
#166 December 03, 2021
Speaker: Aleksandra Baeva
Topic: New trends in the description of non-Markovian quantum processes (based on the report of Sergey Filippov at QTS’21)
Link to Zoom: https://us04web.zoom.us/j/4718938781?pwd=cHpmY2FmMDVJTFk4N1NHYkhVNW1UZz09
OR Zoom ID number: 471 893 8781
Pasword: 1234
#165 November 26, 2021
Speaker: Daniil Reshetnikov
Topic: Complex Kähler manifold and quantum coherence (based on the report of A.V. Gorohov at PECS-2021)
#164 November 19, 2021
Speaker: Elizaveta Bashmakova
Topic: Quantum control of ions for quantum computations and frequency standards
Links to Youtube: part1 - part2 - part3
#163 November 12, 2021
Speaker: Evgenii Vashukevich
Topic: По материалам доклада С.А. Моисеева и Р.В. Урманчеева "Теорема площадей фотонного эха в резонаторе и оптически плотной среде", сделанного на XII международном симпозиуме по фотонному эхо и когерентной спектроскопии ФЭКС-2021.
Links to Youtube: part1 - part2
#162 October 29, 2021
Speaker: Viacheslav Kuzmin (Center for Quantum Physics, University of Innsbruck, Innsbruck A-6020, Austria)
Topic: Probing infinite many-body quantum systems with finite-size quantum simulators (https://arxiv.org/abs/2108.12378)
Abstract: Экспериментальные исследования синтетических квантовых материалов неизбежно ограничены конечностью контролируемой системы призванной симулировать основное состояние изучаемой системы. Для материалов с длиной квантовой корреляции превышающей размеры доступной системы данное конечно-размерное приближение перестает быть точным. Такая ситуация например возникает вблизи квантового фазового перехода второго рода. Я расскажу о протоколе позволяющем напрямую приготовить матрицу плотности подсистемы бесконечной трансляционно-инвариантной системы в конечном квантовом симуляторе. Последнее достигается с помощью когерентной эволюции с использованием гладкой деформации интересующего Гамильтониана которая приводит к перемещению низкоэнергетических квазичастиц из центра к границам симулятора реализуя, в центре, локальный “вакуум” бесконечной квантовой системы. Я проиллюстрирую протокол на примере свободных фермионов в одномерном и двумерном случае. Так же, на примере неинтегрируемой расширенной Su-Schrieffer-Heeger модели [1], я покажу что наш протокол позволяет более точное изучение квантовых фазовых переходов, как с нарушением симметрии так и топологических.
[1] Elben A., et al. Many-body topological invariants from randomized measurements in synthetic quantum matter. Science Advances, 6(15):1–9, 2020.
#161 October 22, 2021
Speaker: Sergey Korolev
Topic: Ancilla-driven quantum computation
#160 October 15, 2021
Speaker: Evgenii Vashukevich
Topic: Spin-Wave Quantum Computing with Atoms in a Single-Mode Cavity
#159 October 08, 2021
Speaker: Emil Davletov (Quantum Simulators And Integrated Photonics (Head of the Lab - A. Akimov), RQC)
Topic: Adaptive planning of an experiment for evaporative cooling of a thulium atom
#158 October 01, 2021
Speaker: Aleksandr Losev
Topic: According to the article G.S. Thekkadath, B.A. Bell, I.A. Walmsley, and A.I. Lvovsky. Engineering Schrödinger cat states
with a photonic even-parity detector. Quantum 4, 239 (2020). DOI: https://doi.org/10.22331/q-2020-03-02-239
#157 September 24, 2021
Speaker 1: Prof. I.V. Sokolov (the continuation of the report)
Topic: Trisqueezed states as a resource for quantum computing
Speaker 2: Aleksandra Baeva
Topic: Protocols of conversion of a trisqueezed state into a qubic phase state
#156 September 17, 2021
Speaker: Prof. I.V. Sokolov
Topic: Trisqueezed states as a resource for quantum computing
Link to Youtube: link
#155 September 10, 2021
Speaker: Igor Mekhov, Senior Researcher, Department of Optics, SPbU
Topic: Quantum measurements as a new source of competitions in many-body physics
#154 June 15 (Tuesday), 2021 at 14:30 room #203-Б
Speaker: Prof. Viktor Mikhailovich Petrov (ITMO)
Topic: Quantum measurements as a new source of competitions in many-body physics
#153 June 04, 2021
Speaker: Dmitrii Frolovtsev (MSU)
Topic: Quantum Computing Platform IBM Q Experience
Abstract: Будут рассмотрены физические принципы, лежащие в основе работы квантовых компьютеров IBM, а также примеры решения нескольких задач на квантовом компьютере — проверки неравенств Белла, квантовая томографии и алгоритма Шора.
#152 May 28, 2021
Speaker: Boris Nasedkin (Laboratory of Quantum Processes and Measurements, ITMO University)
Topic: Spectral vulnerabilities of quantum data transmission systems
#151 May 21, 2021
Speaker: Eduard Zinatullin
Topic: Teleportation error decrease using the cubic phase gate
#150 May 14, 2021
Speaker: Sergey Korolev
Topic: Continuous-variable topological quantum computation
#149 April 30, 2021
Speaker: Aleksandra Baeva
Topic: Qudit-based quantum computing
#148 April 23, 2021
Speaker: Andrey Prokshin
Topic: The Hong-Ou-Mandel effect and its experimental manifestation
#147 April 16, 2021
Speaker: Sergey Korolev
Topic: Quantum computation models
#146 April 02, 2021
Speaker: Prof. Anatoly Stepanovich Chirkin (Lomonosov Moscow State University)
Topic: A new approach to calculating the natural width of optical parametric oscillators (OPO): the frequency deviation operator and general formula for the spectral line width
#145 March 26, 2021
Speaker: Nikolay Larionov (Peter the Great St. Petersburg Polytechnic University)
Topic: Formation of Quantum Vortices at the Ionization of an Atom by an Ultrashort Laser Pulse
#144 March 19, 2021
Speaker: Evgenii Vashukevich
Topic: Quantum gates for qudits with orbital angular momentum
#143 March 12, 2021
Speaker: Prof. T.Yu. Golubeva
Topic: CZ vs Beamsplitter: errors of entangled operations
#142 March 05, 2021
Speaker: Natalia Masalaeva
Topic: Quantum statistics of Schrödinger cat states prepared by logical gate with non-Gaussian resource state
#141 February 26, 2021
Speaker: Kirill Tikhonov
Topic: Cumulants and measures of non-gaussinity for quantum states
#140 February 19, 2021
Speaker: Kirill Tikhonov
Topic: Cumulants and measures of non-gaussinity for quantum states
#139 February 12, 2021
Speaker: Dmitrii Tsarev
Topic: Mesoscopic superposition states of bright solitons for quantum metrology
Abstract: Доклад посвящен теории формирования мезоскопических запутанных состояний квантовых солитонов, а также их применению в квантовой метрологии в присутствии потерь. Рассмотрен новый подход к описанию материальных светлых солитонов с относительно небольшим числом частиц и предложено устройство квантовых солитонных Джозефсоновских контактов, которое позволяет сформировать относительно устойчивые к потерям запутанные состояния Фока для числа частиц в солитонах. Выявлены условия, при которых эти состояния могут быть задействованы в схемах с квантовой метрологией для достижения так называемого предела Гейзенберга оценки фазовых параметров.
#138 February 05, 2021
Speaker: Ranjit Singh
Topic: Backward four-photon mixing in ghost imaging
Sup. material: http://www.jetp.ac.ru/cgi-bin/e/index/r/159/2/p258?a=list
#137 January 29, 2021
Speaker: Aleksandr Losev
Topic: Far Off-Resonance Duan–Lukin–Cirac–Zoller protocol (FORD protocol)
Sup. material: J.-P. You et al. A broadband DLCZ quantum memory in room-temperature atoms. Commun. Phys. 1, 55 (2018).
#136 January 22, 2021
Speaker: Eduard Zinatullin
Topic: Resource theory of quantum non-Gaussianity and Wigner negativity
#135 January 15, 2021
Speaker: Anton Vetlugin
Topic: Deterministic generation of entanglement in quantum network by distributed coherent absorption of a single photon
#134 December 18, 2020
Speaker: Denis Vasilyev
Topic: Quantum non-demolition measurement of a many-body Hamiltonian
Link to youtube: link
#133 December 04, 2020
Speaker: Ivan Ryzhov
Topic: Information capabilities of spin noise spectroscopy applied to the study of quantum simulators based on exciton-polariton condensates
#132 November 27, 2020
Speaker: Alisa Manukhova
Topic: Matrix elements of the output state of an ideal QND gate for various types of input with respect
to the Hong-Ou-Mandel effect
Link to youtube: link
#131 November 20, 2020
Speaker: Aleksandr Mikhailov
Topic: Quantum entanglement criterion based on Fisher information
#130 November 06, 2020
Speaker: Daniil Reshetnikov
Topic: Radial Index of Laguerre-Gauss Modes
Speaker: Denis Sychev
Topic: Thomson's Spinning Top and Coherent Population Trapping in the V-scheme
#129 October 30, 2020
Speaker: Natalia Masalaeva
Topic: Quantum simulators using an optical cavity
Links to youtube:
#128 October 23, 2020
Speaker: Evgeniy Vashukevich
Topic: Generation of extreme-ultraviolet beams with time-varying orbital angular momentum
#127 October 16, 2020
Speaker: Sergey Korolev
Topic: High-Threshold fault-tolerant quantum computation in continuous variables
#126 October 09, 2020
Speaker: Aleksandra Baeva
Topic: Quantum tomography, based on the lecture by A.V. Masalov at the International School of Quantum Computing, Sochi, September 14-21, 2020
Speaker: Elizaveta Bashmakova
Topic: Algebraic approachs to driven quantum systems, based on the report by D. Kurlov, Sochi, September 14-21, 2020
#125 October 02, 2020
Speaker: Eduard Zinatullin
Topic: Non-Gaussian statistics of extreme events in stimulated Raman scattering
#124 September 25, 2020
Speaker: Kirill Tikhonov
Topic: Simulation of implementation of randomized quantum algorithms in arrays of neutral atoms
Link to youtube: https://www.youtube.com/watch?v=Lmagt5K0AJQ&t=1576s
#123 September 11, 2020
Speaker: Aleksandr Losev
Topic: Chiral relations and radial-angular coupling in nonlinear interactions of optical vortices. W.T. Buono et al. PRA 101, 043821 (2020).
#122 March 20, 2019 (CANCELED due to COVID-19)
Speaker: Ivan Ryzhov
Topic: Spectroscopy of polarization fluctuations of light: from magneto-optics of paramagnetic media to research of hidden polarization states
Abstract: Доклад посвящён новому оптическому методу исследований — спектроскопии поляризационных флуктуаций света, более известной под названием спектроскопии спиновых шумов (ССШ). Техника ССШ изначально ориентирована на оптические исследования электронного парамагнитного резонанса и позволяет регистрировать магнитное расщепление в спектрах шумов фарадеевского или керровского вращения зондирующего света. ССШ показала свою многофункциональность в исследованиях магнитных и оптических свойств атомных паров, полупроводниковых структур и — в последнее время — диэлектриков, активированных примесными ионами. Однако помимо уже ставшей классической схемы регистрации, в которой исследуемая среда зондируется лазерным светом в области прозрачности, значительную информативность обнаружило применение поляриметрической техники регистрации к излучённому свету. В докладе представлены последние результаты по исследованиям бозе-эйнштейновских конденсатов экситон-поляритонов в планарных полупроводниковых резонатарах Фабри–Перо.
#121 March 13, 2019
Speaker: Alisa Manukhova (Postdoc, Department of Optics, Palacky University, Czech Republic)
Topic: Bunching effect for the phonons of different nature via the atom-mechanical QND gate
Abstract: The report is devoted to the creation and possibilities of a physical implementation of the QND gate based on two physical platforms, which are the collective atomic spin and the mechanical oscillator of the optomechanical cell. The gate is active and generates correlations. One of the examples is the phonon grouping effect, similar to the Hong-Ou-Mandel effect, in which the QND gate acts as a beam splitter, and the input states are the initial single phonon states of the spin and mechanical oscillators.
#120 February 28, 2020
Speaker: Ivan Vadimovich Sokolov.
Topic: Creating Schrodinger cats in a non-Gaussian logic gate for continuous variables
Abstract: In a logic cell providing a non-Gaussian interaction of main and secondary oscillators (a cubic phase gate), a small change allows you to turn an arbitrary state of the main oscillator into Schrodinger cat. I.e. to split the original wave function into two distinguishable components.
#119 February 21, 2019
Speaker: Sergey Sysoev (Department of Software Engineering, Faculty of Mathematics And Mechanics, SPBU)
Topic: Analysis of Unitarity of the Modified Grover Algorithm
#118 February 14, 2020
Speaker: Mansur Minnegaliev (Kazan Quantum Center (in KNRTU-KAI), Laboratory of Quantum Memory)
Topic: Optical quantum memory in crystals doped by rare-earth ions and its implementation in an optical cavity
Annotation: The report is devoted to the experimental realization of optical memory based on photon echo approach in crystals doped by rare-earth ions. The first part of the report presents the results of the implementation of the revival of silenced echo quantum memory protocol in an impedance-matched optical cavity using a Tm3+: Y3Al5O12 crystal and demonstration of addressable writing and reading of input signals. The second part of the report presents the results of a spectroscopic study of an Er3+: 7LiYF4 crystal to assess the feasibility of realizing an off-resonant Raman echo quantum memory scheme in this crystal.
#117 February 07, 2020
Speaker: Sergey Korolev
Topic: Entanglement criterion based on Fisher information
#116 December 20, 2019
Speaker: Mikhail Saygin (Center for Quantum Technology, MSU)
Topic: Linear optical platform for quantum computing. Problems and prospects.
#115 December 13, 2019
Speaker: Sergey Sysoev (Department of Software Engineering, Faculty of Mathematics And Mechanics, SPBU)
Topic: The illusion of optimality. The proof is true, but is the theorem chosen correctly?
Annotation: The main ideas of quantum algorithms construction will be considered in the report. The greatest attention will be paid to Grover's algorithm, probably the most elegant known to the author of quantum algorithms. For Grover's algorithm, there is proof of its optimality. With this proof in mind, we will try to consider the idea of improving the algorithm. In the event of the very likely failure of this venture, we will gain an in-depth understanding of the structure of the algorithm. Well, in case of success...
#114 December 06, 2019
Speaker: Elizaveta Bashmakova
Topic: Classical And Quantum Description of Dissipative Solitons
#113 November 29, 2019
Speaker: Evgeniy Vashukevich
Topic: Quantum hyperentanglement and its applications in quantum information processing
#112 November 22, 2019
Speaker: Aleksandr Losev
Topic: Quadrature Entanglement of Two-Mode States In Terms of Schmidt Decomposition - Interesting Examples. Continued from October 11
#111 November 08, 2019
Speaker: Sergey Sysoev (Department of Software Engineering, Faculty of Mathematics And Mechanics, SPBU)
Topic: Algorithm theory made friends with quantum mechanics, but why?
Annotation: The report will address the problems of classical computing, the hope for the resolution of which gives a quantum computer. This hope is based on the mathematical model of the universal quantum computer proposed by David Deutsch in 1985. Working within the framework of this model, it is easy to forget (or not to notice) where the advantage of quantum computing over classical comes from. The rationale for this advantage is the main objective of the report.
#110 November 01, 2019
Speaker: Sergey Korolev
Topic: Finding the optimal cluster state configuration for one-way quantum computation
#109 October 25, 2019
Speaker: Kirill Tikhonov
Topic: Representation of The Density Operator by Means of Cumulants. Calculation of Simultaneous And Two-Time Correlation Functions. Part 2.
#108 October 18, 2019
Speaker: Kirill Tikhonov
Topic: Representation of The Density Operator by Means of Cumulants. Calculation of Simultaneous And Two-Time Correlation Functions. Part 1.
#107 October 11, 2019
Speaker: Aleksandr Losev
Topic: Quadrature Entanglement of Two-Mode States In Terms of Schmidt Decomposition
Application: https://arxiv.org/abs/1905.05088
#106 October 04, 2019
Speaker: Ivan Vybornyi
Topic: The Backflash Effect In Quantum Cryptography
#105 September 27, 2019
Speaker: Prof. I.V. Sokolov
Topic: On a non-Gaussian logic gate based on the measurement of the number of photons (GKP model)
#104 September 13, 2019
Speaker: Mikhail Cherkasskii
Topic: Under the article X.Guo, C.-L. Zou, H. Jung, and H.X. Tang. On-Chip Strong Coupling and Efficient Frequency Conversion between Telecom and Visible Optical Modes. PRL 117, 123902 (2016)
#103 September 06, 2019
Speaker: Aleksandr Losev
Topic: The physical meaning of the radial number of the orbital angular momentum
#102 May 24, 2019
Speaker: K.V. Petrovnin
Topic: Broadband multi-cavity systems as applied to quantum memory problems (Широкополосные многорезонаторные системы применительно к задачам квантовой памяти)
Abstract: Разработка полномасштабного квантового компьютера на сверхпроводящих кубитах подразумевает создание квантовой памяти, работающей в микроволновом диапазоне частот. По аналогии с AFC протоколом квантовой памяти на фотонном эхе, структуры, имеющие гребенчатый спектр поглощения, реализуются с помощью высокодобротных резонаторов. В докладе будут освящены такие этапы, как проектирование отдельных микроволновых высокодобротных резонаторов (в том числе работающих на модах шепчущей галереи), построение на их основе структур, имеющих гребенчатые спектры, управление внутренними параметрами таких систем. Будут представлены результаты экспериментов по сохранению электромагнитного импульса в многорезонаторной системе, являющейся прототипом ячейки микроволновой квантовой памяти, на заданный промежуток времени.
#101 April 26, 2019
Speaker: Sergey Korolev
Topic: Linear Optical Quantum Computations
#100 April 19, 2019
Speaker: Natalia Masalaeva
Topic: Quantum sensors based on ultracold atoms (Under the report of V. I. Balykina from "The 2d Russian School on Quantum Technology")
#99 April 12, 2019
Speaker: Valentin Averchenko (Max Planck Institute, Erlangen, Germany)
Topic: Noise analysis of nonlinear interferometer. New method of restoring the spatial modes of spontaneous parametric down conversion
#98 April 05, 2019
Speaker: Sergey Korolev
Topic: Topological Quantum Computations
March 29, 2019 (CANCELED)
Speaker: Prof. Jacob Biamonte (Skoltech, Moscow)
Topic: Universal Variational Quantum Computation.
Location this time: Blue hall, Research Institute of Physics
#97 March 22, 2019
Speaker: Evgeniy Vashukevich
Topic: Under the report of M. V. Chehova from "The 2d Russian School on Quantum Technology".
#96 March 15, 2019
The 1st speaker: Elizaveta Bashmakova
Topic: The orbital angular momentum in quantum electrodynamics.
The 2d speaker: Ivan Vybornyi
Topic: Spin - the own angular momentum of elementary particles. The spinor conception.
#95 March 01, 2019
Speaker: Sergey Korolev
Topic: Quantum code of error correction in continuous variables. Encoding a qubit in an oscillator (сontinuation of the report of January 25).
#94 February 22, 2019
Speaker: Kirill Tikhonov
Topic: Introduction to the quantum theory of error correction - part 2.
#93 February 15, 2019
Speaker: Kirill Tikhonov
Topic: Introduction to the quantum theory of error correction.
#92 January 25, 2019
Speaker: Sergey Korolev
Topic: Quantum code of error correction in continuous variables. Encoding a qubit in an oscillator.
#91 January 18, 2019
Speaker: Evgeniy Vashukevich
Topic: Optomachanics based on OAM exchange
#90 December 21, 2018
Speaker: Sergey Korolev
Topic: Comparison of errors in two one-way computational schemes that use different cluster states
#89 December 14, 2018
Speaker: Leonid Gerasimov
Topic: On the theory of three-dimensional Raman cooling of an atom in an optical dipole trap.
#88 December 07, 2018
Speaker: Alisa Manukhova
Topic: Quantum interface between an optomeсhanical cavity and an atomic ensemble based on QND interactions with light
November 30, 2018 (CANCELED)
Speaker: Sergey Korolev
Topic: Comparison of errors in two one-way computational schemes that use different cluster states
#87 November 23, 2018
Speaker: Evgeniy Vashukevich
Topic: Experimental realizations of quantum memory for light with orbital angular momentum
#86 November 16, 2018
Speaker: Natalia Masalaeva
Topic: Report on the results of the summer internship at the Institute of Theoretical Physics, Innsbruck "The influence of the non-adiabatical potential on the distribution of atoms inside the cavity"
#85 November 02, 2018
Speaker: Aleksandr Losev
Topic: Quantum Tomography and Light with Orbital Angular Momentum
Abstract: Under the articles
Nicolas et al., “Quantum State Tomography of Orbital Angular Momentum Photonic Qubits via a Projection-Based Technique.” New Journal of Physics 17, no. 3, 033037 (2015). https://doi.org/10.1088/1367-2630/17/3/033037.
Nicolas et al., “A Quantum Memory for Orbital Angular Momentum Photonic Qubits.” Nature Photonics 8, no. 3, 234–38 (2014). https://doi.org/10.1038/nphoton.2013.355.
#84 October 26, 2018
Speaker: Sergey Korolev
Topic: Generating pure single-photon states via spontaneous four-wave mixing in a system of coupled microresonators.
#83 October 19, 2018
Speaker: Eduard Zinatullin
Topic: The influence of termal motion in the multimode quantum memory.
#82 October 12, 2018
Speaker: Prof. Aleksei Akimovich Toropov (PTI Ioffe)
Topic: Single-photon sources for quantum Informatics.
Abstract: В докладе рассмотрены физические принципы и особенности генерации однофотонных состояний в гетероструктурах с одиночными эпитаксиальными полупроводниковыми квантовыми точками и представлены оригинальные данные по разработке и оптическим исследованиям источников однофотонного излучения видимого спектрального диапазона, предназначенных для функционирования в системах квантовой криптографии и линейных оптических квантовых вычислений.
#81 October 5, 2018
Speaker: Natalia Masalaeva
Topic: Cavity-assisted atomic Raman memories beyond the bad-cavity limit: effect of four-wave mixing.
#80 September 28, 2018
Speaker: Ivan Vyborny
Topic: Summer school at KAUST University, Saudi Arabia. Visible light communication (VLC).
#79 September 21, 2018
Speaker: Kirill Tikhonov
Topic: Prospects for a Millihertz-Linewidth Laser.
#78 September 14, 2018
Speaker: Mikhail Cherkasskii
Topic: Spontaneous emission of a V-type three-level atom.
#77 September 07, 2018
Speaker: Sergey Korolev
Topic: Universal quantum computations on two-node cluster states.
#76 May 25, 2018
Speaker: Sergey Korolev
Topic: General scheme of continuous-variable cluster state computations.
#75 May 18, 2018
Speaker: Alisa Manukhova
Topic: Generation of the material-field cluster state and implementation of the logical two-qubit operation CZ on its basis.
#74 May 11, 2018
Speaker: Evgeniy Vashukevich
Topic: Orbital Angular Momentum Multimode Quantum State of Light Generated by Non-Degenerate TROPO Below and Above Threshold.
#73 May 04, 2018
Speaker: Aleksandr Losev
#72 April 27, 2018
Speaker: Mikhail Romanovskiy and Eduard Zinatullin
Topic: Two short reports of 4th-year students on the topics of their final qualification works.
#71 April 13, 2018
Speaker: Andrey Rakhubovsky (Department of Optics, Palacký University, Olomouc, Czech Republic)
Topic: Quantum entanglement in thermal optomechanical system
Abstract: По статье A.A. Rakhubovsky, R. Filip. Robust entanglement with a thermal mechanical oscillator. Phys. Rev. A 91, 062317 (2015).
В работе исследуется гауссова квантовая перепутанность в оптомеханической системе, возникающая в импульсном протоколе, предложенном в [Hofer, 2011] и осуществленном в [Palomaki, 2013]. Показано, что такой протокол значительно менее восприимчив к температуре механической моды, чем предполагается в этих статьях, и что использование надлежащего критерия перепутанности (логарифмической отрицательности) в теории позволяет детектировать последнюю при относительно высоких температурах.
Литература:
- S. G. Hofer, W. Wieczorek, M. Aspelmeyer, K. Hammerer. Quantum entanglement and teleportation in pulsed cavity optomechanics. Phys. Rev. A 84, 052327 (2011).
- T. A. Palomaki, J. D. Teufel, R. W. Simmonds, K. W. Lehnert. Entangling Mechanical Motion with Microwave Fields. Science 342, 710–713 (2013).
#70 April 06, 2018
Speaker: Natalia Masalaeva
Topic: Under the article P.B.R. Nisbet-Jones, J. Dilley, A. Holleczek, O. Barter and A. Kuhn. Photonic qubits, qutrits and ququads accurately prepared and delivered on demand. New J. Phys. 15, 053007 (2013).
#69 March 30, 2018
Speaker: Denis Ivanov
Topic: Schrödinger Stochastic Equation. The Second Part.
#68 March 23, 2018
Speaker: Denis Ivanov
Topic: Schrödinger Stochastic Equation. The First Part.
#67 March 16, 2018
Speaker: Kirill Tikhonov
Topic: Report on materials of the conference "Quantum Optics 2018" held in Obergurgl, Tirol (Austria)
#66 March 02, 2018
Speaker: Alisa Manukhova
Topic: Generation of photonic pairs in a four-wave mixing scheme. Under the article L. Podhora, P. Obšil, I. Straka, M. Ježek, and L. Slodička. Optics Express 25 (25), 31230 (2017)
#65 February 16, 2018
Speaker: Aleksandr Losev
Topic: Greenberger-Horne-Zeilinger state
#64 February 02, 2018
Speaker: Aleksandr Losev
Topic: Orbital-Angular-Momentum and Experimental Realization of GHZ-state on optical qutrits
(the report under the article arXiv:1708.03881 [quant-ph])
#63 January 26, 2018
Speaker: Sergey Korolev
Topic: Criteria of minimum squeezing for generation of any given topology cluster state
January 19, 2018 (CANCELED)
Speaker: Aleksandr Losev
Topic: Orbital-Angular-Momentum and Experimental Realization of GHZ-state on optical qutrits
(the report under the article arXiv:1708.03881 [quant-ph])
#62 January 12, 2018
Speaker: Kirill Tikhonov
Topic: The report under the article M.T. Manzoni, M. Moreno-Cardoner, A. Asenjo-Garcia, J.V. Porto, A.V. Gorshkov, and D.E. Chang. Optimization of photon storage fidelity in ordered atomic arrays. // https://arxiv.org/abs/1710.06312.
#61 December 22, 2017
Speakers (our young students): Ivan Semenov (1-year), Ivan Vyborny (2-year), Elizaveta Bashmakova (2-year), Maria Fedorova (3-year), Aleksandra Baeva (3-year)
Topic: their progress of this half year
#60 December 15, 2017
Speakers: (1) Eduard Zinatullin and (2) Mikhail Romanovskiy
Topic (two short reports): (1) The account of thermal motion in the scheme of multimodal quantum memory. (2) The effect of electromagnetically induced transparency in problems of quantum optics
#59 December 08, 2017
Speaker: Igor Smol'nikov
Topic: Comparison of the measurement-based quantum feedback and coherent quantum feedback schemes
#58 December 01, 2017
Speaker: Pavel Aleksandrovich Petrov (ITMO)
Topic: The study of the interaction of transferred objects from the surface of transparent dielectric materials (on the basis of the candidate's thesis)
Abstract: В докладе представлены результаты исследования взаимодействия возбужденных атомов с поверхностью прозрачных диэлектриков. Исследование выполнено на примере модельной системы, состоящей из атомов рубидия, заключенных в вакуумную сверхтонкую оптическую ячейку (СТЯ) с сапфировыми окнами, а также с использованием времяпролётной методики в вакуумной сантиметровой оптической ячейке с сапфировым окном. Возбуждение атомов рубидия в СТЯ происходило в состояние 5D5/2, под действием излучения двух непрерывных полупроводниковых лазеров, настроенных на соответствующие атомные переходы. Была исследована зависимость интенсивности флуоресценции с оптически не возбуждаемого уровня 6P3/2 от толщины зазора и давления паров. Получено, что при малых давлениях насыщенного пара, зависимость интенсивности от толщины имеет показатель степени близкий к двойке. Получены спектры возбуждения флуоресценции с уровня 6P3/2 при резонансной и не резонансной настройке лазера на переходе 5S1/2 à 5P3/2. Благодаря малой толщине кюветы, столкновения атомов с поверхностью сапфировых окон кюветы происходят чаще, чем столкновения атомов между собой, что позволяет извлечь информацию о взаимодействии атомов с поверхностью твердого тела. Исследования по времяпролётной методике позволили определить глубину адсорбционного потенциала пары рубидий-сапфир. Определены условия перехода от фотодесорбции к тепловому процессу десорбции. Исследования зависимости кинетической энергии десорбированных атомов от длины волны десорбирующего излучения, привели к неожиданному результату: при увеличении энергии десорбирующего кванта средняя кинетическая энергия десорбированных атомов уменьшается. Обсуждаются возможные причины обнаруженного явления.
#57 November 24, 2017
Speaker: Sergey Korolev
Topic: Implementation of the CZ transformation on a linear cluster state
#56 November 17, 2017
Speaker: Evgeniy Vashukevich
Topic: The introduction of orbital angular momentum in classical and quantum electrodynamics
#55 November 03, 2017
Speaker: Kirill Tikhonov
Topic: The report under article J. Borregaard, M. Zugenmaier, J.M. Petersen, H. Shen, G. Vasilakis, K. Jensen1, E.S. Polzik & A.S. Sørensen
#54 October 27, 2017
Speaker: Natalia Veselkova
Topic: "Nonstationary and relaxation phenomena in quantum memory based on an optical cavity"
#53 October 20, 2017
Speaker: Natalia Masalaeva
Topic: "Stochastic Master Equations"
#52 October 13, 2017
Speaker: Oleg Mikhailovich Marchenko
Topic: "Experiment on correlation of entangled photons"
#51 October 06, 2017
Speaker: Aleksandr Losev
Topic: "Nonlinear Interaction between Single Photons" (PRL 113, 173601 (2014))
#50 September 29, 2017
Speaker: Sergey Korolev
Topic: The Einstein–Podolsky–Rosen Paradox, Hidden Variables, and Bell's Theorem
#49 September 15, 2017
Speaker: Sergey Korolev
Topic: The Einstein–Podolsky–Rosen Paradox, Hidden Variables, and Bell's Theorem
#48 September 8, 2017
Speaker: Sergey Korolev
Topic: The Einstein–Podolsky–Rosen Paradox, Hidden Variables, and Bell's Theorem
#47 May 26, 2017
Speaker: Alisa Manukhova
Topic: The shape transformation of a signal without introducing an additional noise, and generation of cluster state with the help of quantum memory cells
#46 May 19, 2017
Speaker: Aleksandr Losev
Topic: D.R.M. Arvidsson-Shukur and C.H.W. Barnes "Quantum Counterfactual Communication Without a Weak Trace"
#45 May 5, 2017
Speaker: Aleksandr Losev
Topic: H. Salih, Z.-H. Li, M. Al-Amri, and M.S. Zubairy "Protocol for Direct Counterfactual Quantum Communication", PRL 110, 170502 (2013).
#44 April 28, 2017
Speaker: Sergey Korolev
Topic: A.E. Ulanov, D. Sychev, A.A. Pushkina, I.A. Fedorov, and A.I. Lvovsky "Quantum Teleportation Between Discrete and Continuous Encodings of an Optical Qubit" Phys. Rev. Lett. 118, 160501(2017) – Published 17 April 2017
#43 April 21, 2017
Speaker: Kirill Tikhonov
Topic: Obtaining Cluster States Using Integrated Optics
#42 April 14, 2017
Speaker: three students of 4th-years
Topic: Three reports about discoveries in the field of quantum optics which were awarded the Nobel prize for the last 20 years.
#41 April 7, 2017
Speaker: Ivan Borisovich Bobrov (MGU)
Topic: Spatial correlations in biphotonic and classical fields (submitted for the degree of candidate of physical and mathematical sciences. SPBU is the main opposing organization)
#40 March 24, 2017
Speaker: Sergey Korolev and prof. Yu. M. Golubev
Topic:
(1) End of Sergey's talk "Generation of cluster states in optomechanical quantum systems"
(2) Van Loock-Furusawa Criteria
#39 March 17, 2017
Speaker: Sergey Korolev
Topic: Generation of cluster states in optomechanical quantum systems
#38 March 10, 2017
Speaker: Natalia Veselkova
Topic: Influence of nonadiabaticity on the efficiency of cavity-based quantum memory
#37 March 3, 2017
Speaker: Kirill Tikhonov
Topic: On the article I. Schwartz et al "Deterministic Generation of a Cluster State of Entangled Photons"
#36 February 17, 2017
Speaker: Natalia Masalaeva
Topic: Report under article E. Bimbard et al. "Homodyne Tomography of a Single Photon Retrieved on Demand from a Cavity-Enhanced Cold Atom Memory" Phys. Rev. Lett. 112, 033601
#35 February 10, 2017
Speaker: Prof. S.A. Pulkin
Topic: Experimental research of induced superradiance by femtosecond pulses in rubidium vapor
Abstract: Обсуждаются результаты экспериментального исследования индуцированного фемтосекундными импульсами (в т.ч. импульсами от комб-генератора fs- лазера) сверхилучения. Квадратичная зависимость выходной интенсивности сверхизлучения от входной интенсивности, зависимость от концентрации атомов, малая расходимость и уменьшение на 2 порядка времени релаксации свидетельствуют о кооперативном (коллективном) характере явления.
#34 February 3, 2017
Speaker: S. Korolev
Topic: Computing on cluster states
#33 January 13, 2017
Speaker: Л.В. Герасимов, Д.В. Куприянов (СПбПУ)
Topic: Когерентный контроль рассеяния света в неупорядоченных системах холодных атомов
Abstract: Сообщение будет, в основном, построено по материалам четвёртой главы диссертации, посвящённой описанию физического принципа диффузионного протокола квантовой памяти для света. Главной особенностью рассматриваемой схемы является то, что сигнальный импульс света, состояние которого отображается ("записывается") на состояние атомной подсистемы, распространяется внутри атомной среды в условиях пленения излучения, вследствие чего оптический путь излучения в этой среде может быть эффективно увеличен.
#32 December 23, 2016
Speaker: V. Kuzmin
Topic: A model of 2D quantum repeater, based on the DLCZ protocol
#31 December 16, 2016
Two reports of our students.
Speaker 1: D. Kropotov (bachelor of the 4th year) "The Scattering Operator"
Speaker 2: I. Smol'nikov (bachelor of the 4th year): "The Wigner Function of Gaussian States"
#30 December 9, 2016
Three short reports of our students.
Speaker 1: A. Baeva (bachelor of the 2nd year) "Hanbury-Brown-Twiss experiment and its development"
Speaker 2: M. Fedorova (bachelor of the 2nd year): "The protocol of quantum teleportation E91"
Speaker 3: E. Zinatullin (bachelor of the 3d year): "Thin hologram"
#28 November 25, 2016
Speaker: Dmitry Efimov (St.Petersburg State University)
Topic: Features of the Autler-Townes-type spectra in the formation of dressed states in a nondegenerate hyperfine structure of atomic levels
#27 November 18, 2016
Speaker: Natalia Masalaeva
Topic: Effective Hamiltonian for Parametric Luminescence in Quantum Memory System
Abstract: Using Perel Konstantinov diagrams the effective hamiltonian for lambda scheme will be considered. The hamiltonian generates an entanglement between the field mode in a cavity and the spin mode of a medium.
#26 October 28, 2016
Speaker: Valentin Averchenko (Max-Planck-Institut für die Physik des Lichts)
Topic: Laser of ultra-short pulsed Fock states based on SIT and coherent mode locking
#25 October 21, 2016
Speaker: Prof. I.V. Sokolov
Topic: Perel'-Konstantinov diagrams for the density matrix in problems of quantum optics. Lecture 3.
#24 October 14, 2016
Speaker: Prof. I.V. Sokolov
Topic: Perel'-Konstantinov diagrams for the density matrix in problems of quantum optics. Lecture 2.
#23 October 07, 2016
Speaker: Prof. I.V. Sokolov
Topic: Perel'-Konstantinov diagrams for the density matrix in problems of quantum optics. Lecture 1.
#21 September 23, 2016
Speaker: Aleksej Kurapcev, Igor Mikhailovich Sokolov
Topic: Features of cooperative effects in an ensemble of point-like impurity centers in Fabry-Perot cavity
#20 September 09, 2016
Speaker: Aleksandr Losev
Topic: Beam Splitting based on Light Storage in Tripod-Type Atomic Ensemble. Experiments.
#19 September 02, 2016
Speaker: Alisa Manukhova
Topic: Circuit Quantum Electrodynamics (on the proceedings of the symposium held this summer in Benasque "Quantum Science: Implementations")
#18 May 10, 2016
Speaker: Denis Vasilyev
Topic: Stochastic dynamics of a quantum system under continuous measurement
#17 April 26, 2016
Speaker: Sergey Korolev
Topic: Cluster states in continuous variables
#16 April 12, 2016
Speaker: Sergey Korolev
Topic: Cluster states in discrete variables
#15 April 05, 2016
Speaker: Prof. A.S. Chirzov
Topic: The discussion on quantum images
#14 March 29, 2016
Speaker: PhD, ass. prof. Nikolay Larionov, Peter the Great St. Petersburg Politechnic University
Topic: Non-classical behavior of Glauber function averaged over the P phase for a single-emitter nanolaser". Continuation.
#13 March 22, 2016
Speaker: PhD, ass. prof. Nikolay Larionov, Peter the Great St. Petersburg Politechnic University
Topic: Non-classical behavior of Glauber function averaged over the P phase for a single-emitter nanolaser"
#12 March 15, 2016
Speaker: Kirill Tikhonov
Topic: On the article by N. Korolkova "Nonlinear dissipation can combat linear loss"
#11 March 01, 2016
Speaker: Aleksandr Losev
Topic: Non-Abelian quasiparticles (Majorana fermions) and topological quantum computing (in Russian)
#10 February 09, 2016
Speaker: Prof. Natalia Korolkova (University of St Andrews, Scotland)
Topic: Quantum Light: Quantumness of Correlations and their applications (in Russian)
Abstract: In this talk I describe the nature of non-classical correlation beyond entanglement. Quantum discord is introduced as a measure of such quantum correlations and compared to some other measures. The role of system-environment coupling in dynamics of these correlations and some operational interpretations of discord are discussed, in particular activation of correlations into entanglement. The quantum nature of correlations is illustrated with an example of bright light beams. In this context, some illuminating quantum information protocols based on quantum correlations in optical modes are briefly described.
#9 December 25, 2015
Speaker: Anton Vetlugin
Topic: On materials of thesis (in Russian)
#8 December 18, 2015
Speaker: Sergey Korolev
Topic: Concurrence as a criterion of entangled state. Quantum discord (continuation) (in Russian)
#7 December 4, 2015
Speaker: Sergey Korolev
Topic: Concurrence as a criterion of entangled state. Quantum discord (in Russian)
#6 November 27, 2015
Speaker: Anton Vetlugin
Topic: On materials of thesis (in Russian)
#5 November 20, 2015
Speaker: Aleksandr Losev
Topic: Entanglement atoms interacting with a thermal field
Materials: According to the materials of the conference "Optics-2015" (in Russian)
#4 October 2, 2015
Speaker: Prof. Ivan V. Sokolov
Topic: Control of Quantum States in Memory of Many Degrees of Freedom (continuation) (in Russian)
#3 September 25, 2015
Speaker: Prof. Ivan V. Sokolov
Topic: Control of Quantum States in Memory of Many Degrees of Freedom (in Russian)
#2 September 11, 2015
Speaker: Kirill Tikhonov
Topic: Pre-dissertation (in Russian)
#1 September 4, 2015
Speaker: Aleksandr Losev
Topic: Creating two effectively entangled light pulses by using an ensemble of tripod-type atoms (in Russian)