Mr John Jarman
About
Stable, on-demand single-photon sources that can operate at room temperature will be an enabling technology for applications such as quantum cryptography and quantum computing. Indium gallium nitride quantum dots grown in gallium nitride offer the deep confinement potential required for room temperature single-photon emission, and such dots fabricated on the non-polar (11-20) a-plane of GaN also show the stability that would be required of such emitters.
My research centres on the nanofabrication of optical cavities in GaN. These photonic structures are designed to confine light around the quantum dot, enhancing its emission at a particular wavelength, and are a key step towards the creation of a practical single-photon source. I also work on microfabrication of LED structures such as the one pictured below.
Light emission from a c-plane LED - test structures such as these are used to investigate the behaviour of quantum dots under a variable electric field.
Dark-field optical micrograph of a chrome mask for optical microcavities