A great effort has recently gone into the search for practical architecture for quantum information processing systems. In this paper we focus on optical implementations of quantum information processing systems – in particular quantum phase gate[1]. One of the possible ways to realize this system requires strong interaction of the photonic qubits. Sufficiently strong interactions have been una...

We propose a simple probabilistic optical gate to expand polarization entangled W states. The gate uses one polarization-dependent beamsplitter and a horizontally polarized single photon as an ancilla. The gate post-selectively expands N -photon W states to (N + 1)-photon W states. A feasibility analysis considering the realistic experimental conditions show that the scheme is within the reach ...

Background and Objectives: Recently, photonic crystals have been considered as the basic structures for the realization of various optical devices for high speed optical communication. Methods: In this research, two dimensional photonic crystals are used for designing all optical logic gates. A photonic crystal structure with a triangular lattice is proposed for making NAND, XNOR, and OR optica...

Teleportation of quantum gates is a critical step for the implementation of quantum networking and teleportation-based models of quantum computation. We report an experimental demonstration of teleportation of the prototypical quantum controlled-NOT (CNOT) gate. Assisted with linear optical manipulations, photon entanglement produced from parametric down-conversion, and postselection from the c...

In this paper, we show that anisotropic photosensitive nematic liquid crystals (PNLC) made by incorporating anisotropic absorbing dyes are promising candidates for constructing all-optical elements by virtue of the extraordinarily large optical nonlinearity of the nematic host. In particular, we have demonstrated several room-temperature 'prototype' PNLC-based all-optical devices such as optica...

We consider two new quantum gate mechanisms based on nuclear spins in hyperpolarized solid Xe and HCl mixtures and inorganic semiconductors. We propose two schemes for implementing a controlled NOT ( CNOT ) gate based on nuclear magnetic resonance ( NMR ) spectroscopy and magnetic resonance imaging ( MRI ) from hyperpolarized solid Xe and HCl mixtures and optically pumped NMR in semiconductors....

Creation of large-scale W state quantum networks is a key step for realization of various quantum information tasks. Regarding the photonics technology, a simple optical setup was proposed for the fusion of two W states. Recently it was shown that via a single Fredkin gate, this basic so-called fusion setup can be enhanced. However the main problem was that the probability of success of realiza...

The majority of linear-optical nondestructive implementations of universal quantum gates are based on single-photon resolving detectors. We propose two implementations, which are nondestructive (i.e., destroying only ancilla states) and work with conventional detectors (i.e., those which do not resolve number of photons). Moreover, we analyze a recently proposed scheme of Wang et al. [J. Opt. S...

We report coherent optical control of a biexciton (two electron-hole pairs), confined in a single quantum dot, that shows coherent oscillations similar to the excited-state Rabi flopping in an isolated atom. The pulse control of the biexciton dynamics, combined with previously demonstrated control of the single-exciton Rabi rotation, serves as the physical basis for a two-bit conditional quantu...

In recent past, reversible logic is emerged as a promising computing paradigm with applications in low-power CMOS, quantum computing, optical computing and nanotechnology. Optical logic gates become potential component to work at macroscopic (light pulses carry information), or quantum (single photon carries information) levels with high efficiency. In this paper, we propose a novel scheme of T...