InSb Quantum Electronics - investigating the technology for an electric field controlled, spin-based qubit made from indium antimonide (InSb) and half metallic alloys.

This project will be investigating the technology for an electric field controlled, spin-based qubit made from indium antimonide (InSb) and half metallic alloys. InSb has an extremely large g-factor which is a measure of the interaction between the electron spin and the orbital angular momentum and, at first sight, a large value might be perceived to be a detrimental property as it will lead to a relatively short qubit spin lifetime. Critically, however, it also leads to a very large Rashba effect, which couples the splitting of spin bands to asymmetry in the electron potential such as that imposed by an external electric field. This enables the manipulation of the spin by a voltage, applied by a conventional gate as in a MOSFET, without the need for any externally applied magnetic fields, microwaves or other optical excitation. Huge SOI and Rashba effect have indeed been recently demonstrated in InSb nanostructures with a route to electrical-only spin manipulation proposed. A current consortium involving Cardiff, Warwick, Surrey and Sheffield University are developing technology for an electrical controlled qubit structure. This will involve the novel implementation of a half metallic SET structure for read out and spin injection from and to an InSb 2DEG. This project will be looking at the physics of the half metallic interface with an InSb based QW 2DEG, to develop efficient spin injection and detection down to a single electron level. Half metals will be deposited in house, and under high vacuum with our collaborators at Warwick, and electrical measurements down to mK temperatures will be performed at Cardiff. Interface characterisation will be critical using both imaging technology (SEM and EDX) and CV electrical measurement.

This project will start on 01/10/2018


Please be aware that Cardiff University reserves the right to close this vacancy early should sufficient applications be received.