Optical interferometers comprising birefringent-crystal beam displacers, wave plates, and phase shifters serve as stable devices for simulating quantum information processes such as heralded coined quantum walks. Quantum walks are important for quantum algorithms, universal quantum computing circuits, quantum transport in complex systems, and demonstrating intriguing nonlinear dynamical quantum...

In vivo tissue imaging using near-infrared light suffers from low spatial resolution and poor contrast recovery because of highly scattered photon transport. For diffuse optical tomography (DOT) and fluorescence molecular tomography (FMT), the resolution is limited to about 5-10% of the diameter of the tissue being imaged, which puts it in the range of performance seen in nuclear medicine. This...

High-visibility interference of photon echoes generated in spatially separated solid-state atomic ensembles is demonstrated. The solid-state ensembles were LiNbO(3) waveguides doped with erbium ions absorbing at 1.53 microm. Bright coherent states of light in several temporal modes (up to 3) are stored and retrieved from the optical memories using two-pulse photon echoes. The stored and retriev...

Strong exciton-photon coupling is the result of a reversible exchange of energy between an excited state and a confined optical field. This results in the formation of polariton states that have energies different from the exciton and photon. We demonstrate strong exciton-photon coupling between light-harvesting complexes and a confined optical mode within a metallic optical microcavity. The en...

A Monte Carlo code for the calculation of light transport in heterogeneous scattering media is presented together with its validation. Triangle meshes are used to define the interfaces between different materials, in contrast with techniques based on individual volume elements. This approach allows to address realistic problems in a flexible way. A hierarchical spatial organisation enables a fa...

Photon density wave is the modulated optical intensity wave which propagates through the diffuse medium and exhibits the amplitude and phase variations. It satisfies the time-dependent radiative transfer equation and is similar to temperature wave field, and has been used in medical imaging. This paper discusses the basic characteristics of the photon density wave and gives exact numerical solu...

Integrated quantum optical circuits are now seen as one of the most promising approaches with which to realize single-photon quantum information processing. Many of the core elements for such circuits have been realized, including sources, gates and detectors. However, a significant missing function necessary for photonic quantum information processing on-chip is a buffer, where single photons ...

Previously, we have described a low temperature grown GaAs device that uses single-photon absorption to perform a carrier lifetime limited optical autocorrelation of picosecond optical pulses. In this article, we describe how this same device could be used to perform an autocorrelation of femtosecond optical pulses by utilizing two-photon absorption ~TPA!. Furthermore, we propose how to model a...

Since the first quantum ghost imaging (QGI) experiment in 1995, many QGI schemes have been put forward. However, the position-position or momentum-momentum correlation required in these QGI schemes cannot be distributed over optical fibers, which limits their large-scale geographical applications. In this paper, we propose and demonstrate a scheme for long-distance QGI utilizing frequency corre...

Quantum controlled-phase-flip (CPF) gate between a flying photon qubit and a stationary atomic qubit could allow the linking of distant computational nodes in a quantum network. Here we present a scheme to realize quantum CPF gate between a flying optical photon and an atomic ensemble based on cavity input-output process and Rydberg blockade. When a flying single-photon pulse is reflected off t...