Biomedical subjects

J Fiurásek

Publications and source records attributed to J Fiurásek.

4 recordsLinked to original sources

PubMed2005

Separating the classical and quantum information via quantum cloning.

An application of quantum cloning to optimally interface a quantum system with a classical observer is presented; in particular, we describe a procedure to perform a minimal disturbance measurement on a single qubit by adopting a 1-->2 cloning machine followed by a generalized measurement on a single clone and the anticlone or on the two clones. Such a scheme can be applied to enhance the transmission fidelity over a lossy quantum channel.

Journal Article↗

PubMed2004

Experimental purification of single qubits.

We report the experimental realization of the purification protocol for single qubits sent through a depolarizing channel. The qubits are associated with polarization states of single photons and the protocol is achieved by means of passive linear optical elements. The present approach may represent a convenient alternative to the distillation and error correction protocols of quantum information.

Journal Article↗

PubMed2004

Proposal for a loophole-free Bell test using homodyne detection.

We propose a feasible optical setup allowing for a loophole-free Bell test with efficient homodyne detection. A non-Gaussian entangled state is generated from a two-mode squeezed vacuum by subtracting a single photon from each mode, using beam splitters and standard low-efficiency single-photon detectors. A Bell violation exceeding 1% is achievable with 6 dB squeezed light and a homodyne efficiency around 95%. A detailed feasibility analysis, based upon the recent experimental generation of single-mode non-Gaussian states, suggests that this method opens a promising avenue towards a complete experimental Bell test.

Journal Article↗

PubMed2001

Optical implementation of continuous-variable quantum cloning machines.

We propose an optical implementation of the Gaussian continuous-variable quantum cloning machines. We construct a symmetric N-->M cloner which optimally clones coherent states, and we also provide an explicit design of a class of asymmetric 1-->2 cloning machines. All proposed cloning devices can be built from just a single nondegenerate optical parametric amplifier and several beam splitters.

Journal Article↗