Our research center has a pursuing and vigorous research program in the theory of quantum information and quantum computation. We put emphasis on high-quality training of talented undergraduate and graduate students. RCQI ranks among the top research groups in Slovakia and has established collaborations with numerous research and educational institutions across Europe and North America.

04.02. 13:00 [RCQI]
Denis Kochan (FMFI UK, Bratislava):
Quantization of non-Lagrangian systems

18.02. 13:00 [RCQI]
Andrej Gendiar (RCQI):
Sferická deformácia pre neinteragujúce aj interagujúce fermiónové systémy

25.02. 13:00 [WIEN]
(RCQI):
Nonlocal seminar

currently no visitors

08.02-11.02 Practical Quantum Cryptography Winter School, Les Diablerets, Switzerland
08.02-13.02 46 Karpacz Winter School of Theoretical Physics, Ladek Zdroj, Poland
21.02-26.02 Quantum Optics, Obergurgl, Austria

Research Center for Quantum Information
Institute of Physics, Slovak Academy of Sciences
Dúbravská cesta 9, 84511 Bratislava, Slovakia
Tel: (+421 +2) 20910701
Fax: (+421 +2) 5477-6085

15.1.2010 Equivalent programmable quantum processors by Mark Hillery, Vladimír Bužek, Mário Ziman Programmable quantum circuits, or processors, have the advantage over single-purpose quantum circuits that they can be used to perform more than one function. The inputs of a quantum processor consist of two quantum states, the first, the data register, is a state on which an operation is to be performed, and the second, the program, determines the operation to be performed on the data. In this paper we study how to determine whether two different quantum processors perform the same set of operations on the data. We define an equivalence between quantum processors that is quite natural in a circuit model of quantum information processing. Two processors are equivalent if one can be converted into the other by inserting fixed unitary gates at the input and the output of the program register. We then use this definition to find a necessary condition for two processors to be equivalent. We also study the beam splitter as an example of a quantum processor and find that this example suggests that as well as there being an equivalence relation on processors, there may also be a partial ordering. Published in Optics Communication |+++|

11.1.2010 Quantum theory of unambiguous measurements by Michal Sedlák In the present paper I formulate a framework that accommodates many unambiguous discrimination problems. I show that the prior information about any type of constituent (state, channel, or observable) allows us to reformulate the discrimination among finite number of alternatives as the discrimination among finite number of average constituents. Using this framework I solve several unambiguous tasks. I present a solution to optimal unambiguous comparison of two ensembles of unknown quantum states ... Published in Acta Physica Slovaca |+++|

1.1.2010 Dr. Andrej Gendiar joined our group.

1.1.2010 Dr. Michal Sedlák has (temporarily) left the group. As postdoc he joined group of Prof. D'Ariano in Pavia, Italy.

1.1.2010 Dr. Martin Plesch has left the group and joined Department of Complex Physical Systems at the Institute of Physics, Bratislava.