
Quantum Mechanics: Axiomatics of Measurements and connections
with Computing and Information Retrieval


MILOSLAV
DUSEK, Palacky University 
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VITAE:
Miloslav Dusek is associate professor at the Department of Optics of Palacky
University in Olomouc, Czech Republic. His research activities and interests
cover quantum and coherence optics, quantum entanglement, quantum cryptography,
quantum information processing, and quantum measurement. 

Several
experimental implementations of phase covariant quantum cloner 
aula DOTTORATO  MERCOLEdì 11 ottobre, ore 11.00 
Abstract 


Several experimental realizations of optimal
symmetric probabilistic phasecovariant 1 > 2 cloning of qubit states
is presented. We demonstrate creation of two copies of any state of a
qubit with a fixed latitude on the Poincare sphere (especially of states
lying at its equator). The states of qubits are encoded into polarization
states of photons generated by spontaneous parametric downconversion.
Our devices are based on two main strategies. One of them is the interference
of two photons at a beam splitter with different splitting ratios for
horizontal and vertical polarizations. The other use a quantumstate filtering
based on polarization dependent losses. 
aula DOTTORATO  MERCOLEdì 11 ottobre, ore 14.00 
Experimental realization
of the encoding of two qubits to one qutrit 
Abstract 


We present an optical scheme for
the recently proposed protocol for encoding arbitrary nonentangled states
of two qubits into a state of one qutrit. Our experimental realization uses
spatialmode encoding. I.e., each qudit is represented by a single photon
propagating in d different optical fibers. The compression of two qubits
into one qutrit is realized by an unbalanced beam splitter and a subsequent
measurement. After successful encoding of two qubits the receiver could
errorfree restore any of the two encoded qubit states but not both of them
simultaneously.
The principle of experiment is based on the interplay of the secondorder
and fourthorder interference. Further, we propose certain generalizations
of the original protocol. 

