Optimized preparation of quantum states by conditional measurements

Optimized preparation of quantum states by conditional measurements.

State preparation of quantum systems is a prerequisite for studying fundamental aspects of quantum measurement theory @1#, as well as for encoding quantum information @2# and its processing ~computing! @3#. Problems of state preparation have been dealt with most extensively in the realm of cavity quantum electrodynamics @4–8#. One proposal for state preparation of a cavity field mode @8# relies...

Non-Gaussian states by conditional measurements

We address realistic schemes for the generation of non-Gaussian states of light based on conditional intensity measurements performed on correlated bipartite states. We consider both quantum and classically correlated states and different kind of detection, comparing the resulting non Gaussianity parameters upon varying the input energy and the detection efficiency. We find that quantum correla...

Optimized Design of Multiplexor by Quantum-dot CellularAutomata

Quantum-dot Cellular Automata (QCA) has low power consumption and high density and regularity. QCA widely supports the new devices designed for nanotechnology. Application of QCA technology as an alternative method for CMOS technology on nano-scale shows a promising future. This paper presents successful designing, layout and analysis of Multiplexer with a new structure in QCA technique. In thi...

Pooling quantum states obtained by indirect measurements

Efficient conditional preparation of high-fidelity single photon states for fiber-optic quantum networks.

Highly correlated photons or, accordingly, high-fidelity single-photon states are a prerequisite for closing detection loopholes in experimental tests of local realism and implementing scalable linear optical quantum computation. We demonstrate a parametric down-conversion source exhibiting a conditional detection efficiency of 51% (with corresponding preparation efficiency of 85%) and extraord...