Other

British Telecommunications Public Limited Company

Paul John Cannard

Michael J Robertson

David Graham Moodie

Alexander Giles Davies

Edmund Harold Linfield

Xin Chen

Christopher David Wood

Anthony J Dann

John Cunningham

A method of generating radiation comprises: manufacturing a structure comprising a substrate supporting a layer of InGaAs, InGaAsP, or InGaAlAs material doped with a dopant, said manufacturing comprising growing said layer such that said dopant is incorporated in said layer during growth of the layer; illuminating a portion of a surface of the structure with radiation having photon energies greater than or equal to a band gap of the doped InGaAs, InGaAsP, or InGaAlAs material so as to create electron-hole pairs in the layer of doped material; and accelerating the electrons and holes of said pairs with an electric field so as to generate radiation. In certain embodiments the dopant is Fe. Corresponding radiation detecting apparatus, spectroscopy systems, and antennas are described.

Generating and detecting radiation

A vertical cavity surface emitting laser includes a mirror having first and second layers with first layers containing the elements aluminum, arsenic and antimony and second layers comprising the elements gallium, phosphorus and antimony. Both of these layers are lattice matched to the semiconductor material of the active zone. A VCSEL usually contains two mirrors and, preferably, both mirrors are formed of the elements as specified above. Beryllium can be used to confer p-type conductivity on one mirror and silicon to confer n-type conductivity on the other mirror. Preferably the active zone is formed of semiconductors containing at least one of indium and gallium and at least of phosphorus and arsenic. Conveniently the active zone has a lattice constant substantially equal to that of the indium phosphide and both mirrors are lattice matched to this constant.

Mirrors for semiconductor lasers

Growing community of inventors

Woodbridge, United Kingdom

Paul John Cannard