An intriguing manuscript concerning experimental implementation of quantum memory has recently appeared at arxiv.org. The manuscript is titled “EIT-based photonic memory with near-unity storage efficiency” therein group of ten authors claim that they have achieved 96% storage efficiency in cold Cs vapor using EIT protocol. If the results are correct that is a new record in quantum storage and overall an outstanding experimental result!
Full length text of the authors PhD thesis could be found in a Lobachevsky Nicolay Scientific Library
President Minnikhanov in the Quantum Cryptography lab.
R. Minnikhanov in QC lab.
This Friday in KQC as part of the international youth science and technology conference “Applied electrodynamics, photonics and living systems-2016” there will be held an affiliated meeting titled “Quantum optics and communications“. The session will take place at 10:00 in the conference hall of the center and will feature presenters from several Kazan universities as well as KQC employees.
Each presentation is to be less than 10 minutes long with 5 additional minutes for questions.
Tomorrow 30.03.2016 at 14:00 in Kazan Quantum Center M.R. Mohebbifar from Kazan Federal University will present his work titled
Specialty 01.04.05 Optics
Supervisor: Professor R. Kh. Gainutdinov
Abstract: A quantum key distribution system based on the subcarrier wave modulation method has been demonstrated which employs the BB84 protocol with a strong reference to generate secure bits at a rate of 16.5 kbit/s with an error of 0.5% over an optical channel of 10 dB loss, and 18 bits/s with an error of 0.75% over 25 dB of channel loss. To the best of our knowledge, these results represent the highest channel loss reported for secure quantum key distribution using the subcarrier wave approach. A passive unidirectional scheme has been used to compensate for the polarization dependence of the phase modulators in the receiver module, which resulted in a high visibility of 98.8%. The system is thus fully insensitive to polarization fluctuations and robust to environmental changes, making the approach promising for use in optical telecommunication networks. Further improvements in secure key rate and transmission distance can be achieved by implementing the decoy states protocol or by optimizing the mean photon number used in line with experimental parameters.
This Thursday at 10:00 on scientific seminar Ravil Rashidovich Nigmatullin will present his latest work titled
by R.R. Nigmatullin, proff at KNRTU-KAI, PhD
The authors suggest a general theory for consideration of all experiments associated with measurements of reproducible data in one unified scheme. The suggested algorithm does not contain unjustified suppositions and the final function that is extracted from these measurements can be compared with hypothesis that is suggested by the theory adopted for the explanation of the object/phenomenon studied. This true function is free from the influence of the apparatus (instrumental) function and when the ‘‘best fit’’, or the most acceptable hypothesis, is absent, can be presented as a segment of the Fourier series. The discrete set of the decomposition coefficients describes the final function quantitatively and can serve as an intermediate model that coincides with the amplitude-frequency response (AFR) of the object studied. It can be used by theoreticians also for comparison of the suggested theory with experimental observations. Two examples (Raman spectra of the distilled water and exchange by packets between two wireless sensor nodes) confirm the basic elements of this general theory. From this general theory the following
important conclusions follow:
1. The Prony’s decomposition should be used in detection of the quasi-periodic processes and for quantitative description of reproducible data.
2. The segment of the Fourier series should be used as the fitting function for description of observable data corresponding to an ideal experiment. The transition from the initial Prony’s decomposition to the conventional Fourier transform implies also the
elimination of the apparatus function that plays an important role in the reproducible data processing.
3. The suggested theory will be helpful for creation of the unified metrological standard (UMS) that should be used in comparison of similar data obtained from the same object studied but in different laboratories with the usage of different equipment. 4. Many cases when the conventional theory confirms the experimental data obtained from equipment (where the apparatus function was not taken into account) should be remeasured and some of the competitive theoretical hypothesis can be reconsidered, as
well.
This week’s scientific seminar will be held in the conference room at 11:00 12.02.2016 in the conference room. This 
time there will be two reports:
1) Ravil Urmancheev will update the colleagues on the current research progress in “Area theorem for complicated absorption line”
2) Mansur Minnegaliev is going to present “Review of optical spectroscopy works regarding Pr: LiYF4”
19 of November in the Conference hall of our center at 14:30 Laboratory of quantum memory started their weekly seminar sessions. The first presentation was devoted to the Er3+:Y2SiO5 famous for its homogeneous absorption linewidth of only 73 Hz, which is thinner than in any other known solid state material. The presentation “An overview of properties of Er3+:Y2SiO5 for photon echo” by Ravil Urmancheev touched on the properties of 4I15/2 -> 4I13/2 transition in Er.
| For about two months we had a pleasure of working with Mahmood Sabooni, one of the top experimentalists in the field of optical quantum memory. His group achieved one of the records in solid state photon QM. He helped us set up and carry out the first basic experiments of photon echo and has been just a great person to have around. He has been the first of hopefully many guest researchers in or center needless to say that we have enjoyed his company a lot and hope to see him again next summer. |
 Mahmood |
