Electroluminescence from a single quantum dot within the intrinsic region of a p-i-n junction is shown to act as an electrically driven single-photon source. At low injection currents, the dot electroluminescence spectrum reveals a single sharp line due to exciton recombination, while another line due to the biexciton emerges at higher currents. The second-order correlation function of the diod...

Avalanche Photodiodes (APDs) connected with quenching circuits can be used for single photon detection. This semiconductor photon detector has a better performance than photomultiplier. The principles and applications of APDs are presented. Features, performance of different commercial devices are introduced and compared. Recent research progress based on the improvement of quenching circuits a...

We demonstrate the implementation of a fiber-integrated spectrograph utilizing chromatic group velocity dispersion (GVD) in a single-mode fiber. By means of GVD we stretch an ultrafast pulse in time in order to spectrally resolve single photons in the time domain, detected by single-photon counting modules with very accurate temporal resolution. As a result, the spectrum of a very weak pulse is...

This paper explores the fundamentals and applications of single and entangled photon sources. These sources are the ground works for advances in quantum communications, ranging from quantum cryptography to topics as peculiar as quantum teleportation. Single Photon Sources I. What is a Single Photon Source? A single photon source is an emitter of light that has all of its photons separated in ti...

We present recent results on our development of single photon detectors, including: gated and free-running InGaAs/InP avalanche photodiodes; hybrid detection systems based on sum-frequency generation and Si APDs; and SSPDs (superconducting single photon detectors), for telecom wavelengths; as well as SiPM (Silicon photomultiplier) detectors operating in the visible regime.

631 Photonic technologies are becoming increasingly prevalent in our daily lives. After decades of rapid advances, light sources — especially lasers and light-emitting diodes — have become high-performance, yet low-cost and reliable components, driving the Internet and lighting cities. A new frontier of research is the development of non-classical light sources: sources that produce streams of ...

Single-photon entanglement is a simple form of entanglement that exists between two spatial modes sharing a single photon. Despite its elementary form, it provides a resource as useful as polarization-entangled photons and it can be used for quantum teleportation and entanglement swapping operations. Here, we report the first experiment where single-photon entanglement is purified with a simple...

This report is a synthesis of my master thesis internship at the National Institute of Informatics in Tokyo that last during the summer of year 2012. I worked in the Quantum Information Science Theory (QIST) group under supervision of Prof. Kae Nemoto and Dr. Simon Devitt. The group works on theoretical and experimental implementations of quantum information science. The aim of my project was t...

Abbreviations 2D, 3D 2-dimensional, 3-dimensional CZT cadmium zinc telluride EKG electric signal from the heart FBP filtered backprojection FOV field-of-view GE General Electric Ge(Li) germanium detector doped with lithium MLEM maximum likelihood expectation maximization NaI(Tl) sodium iodine doped with thallium NM nuclear medicine OSEM ordered subset expectation maximization PET positron emiss...

Visible light photon counters (VLPCs) and solid-state photomultipliers (SSPMs) are high-efficiency single-photon detectors which have multi-photon counting capability. While both the VLPCs and the SSPMs have inferred internal quantum efficiencies above 93%, the actual measured values for both the detectors were in fact limited to less than 88%, attributed to in-coupling losses. We are currently...