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Quantum Optics Lab Seminar
 
What:  we make reports on quantum optics

Where:  room #128-A, Department of General Physics 1

When:  on Friday from 11:00 a.m. untill lunch

#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.

 

#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).

 

#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])

 

#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

 

#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"

https://arxiv.org/pdf/1705.05628.pdf

 

#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"

#29 December 2, 2016
Speaker: Kirill Tikhonov

Topic: Combined atomic-field cluster states

#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.

#22 September 30, 2016
Speaker: Aleksandr Losev

Topic:  The Glued Atoms

#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)

 

 

 

#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...