Fujitsu Corporation

Toshio Oshima

Toshiro Futatsugi

Naoki Yokoyama

Toshio Fujii

Akihiro Shibatomi

Kazuaki Ishii

The invention relates to a single-photon generator and a single-photon generating method, which theoretically makes it possible to precisely generate a single photon in real time. A three-level lambda system is formed of a coupled quantum dots group, which is a set of a number of coupled quantum dots where a couple of quantum dots having different ground quantum levels are coupled. The entirety is made in an exciton ground state through illumination with first excitation light. Then, the number of photons in the Raman scattering light through illumination with second excitation light is detected, and a single excited Dicke state is achieved. After that, a single photon is generated accompanying the transition from the single excited Dicke state to the exciton ground state through illumination with third excitation light.

Single photon generator and single-photon generating method

An electrode structure of an electrode of a refractory metal or a silicide thereof on a layer of In.sub.x Ga.sub.1-x As (0&lt;x&lt;1) on a substrate of a III-V compound semiconductor is ohmic and is stable even at a high temperature, for example, 900.degree. C. This high temperature stable ohmic electrode structure allows ion implantation into the substrate with the electrode as a mask followed by annealing to form a doped region in alignment with the edge of the electrode.

Method of forming a high temperature stable ohmic contact to a III-V

A semiconductor device comprises a first barrier layer, a quantum well layer formed on the first barrier layer and having a bottom of conduction band with an energy which varies with a curve of second order, a second barrier layer formed on said quantum well layer, and first and second contact layers. The first barrier layer, the quantum well layer and the second barrier layer make up a layer sequence which is repeated a predetermined number of times, and the first contact layer connects to the first barrier layer in a first of the predetermined number of layer sequences, while the second contact layer connects to the second barrier layer in a last of the predetermined number of layer sequences.

Growing community of inventors

Atsugi, Japan

Toshio Oshima