SAW-driven source of polarised single photons

Research Topic

Surface acoustic waves can confine and transport single electrons while maintaining their spin polarization. The acoustic transport of spin-polarized single electrons across a n-i-p junction followed by recombination with holes should give rise to the emission of single polarized photons at a rate equal to the SAW frequency.


The main goal of the project is to obtain a SAW-driven, polarised, single-photon source based on the acoustic transport of single electrons. The emission is obtained from the recombination of single electrons driven across an undoped n-i-p junction by surface acoustic waves into a region of holes. A proof-of-principle device constitutes the first milestone. I am trying to develop devices in which both electrons and holes are induced in an undoped GaAs/AlGaAs well by gates to form a lateral n-i-p junction. SAWs, generated by a transducer, travel in the n-region and collect electrons which are transported in the p-region where they recombine with the holes. If the stream is composed of single electrons, the recombination with holes should produce a stream of single photons. Furthermore, the recombination of spin-polarised electrons can generate circularly polarised photons, providing a method of spin readout in a quantum computer and a way for conversion of spin qubits into photon qubits.


Antonio Rubino

Host: University of Cambridge

Scientific Background

I obtained my Bachelor degree in Physics from the University of Salerno in 2013 working on Superconducting Nanowire Single-Photon detectors (SNSPDs) based on high temperature superconductors.
In July 2015, I completed a master degree in Physics at the same University, with a thesis on quantum optics at single-photon level. For the latter, I performed most of the experimental activity at Single Quantum BV and at Delft University of Technology, with Erasmus funding. I studied the single-photon emission and two photon interference from a nanowire quantum dot, the improvement of SNSPDs based on NbTiN, and the development of cold filters for the blackbody radiation.

Conference/Workshop Contributions
    • Development of a SAWdriven source of polarised single photons
      A. Rubino, T. K. Hsiao, Y. Chung, A. Nasir, H. Hou, S. K. Son, J. P. Griffiths, I. Farrer, D. A. Ritchie, C. J. B. Ford
      SAWtrain Summer School: Physics and applications of GHz vibrations in semiconductors (Cargèse, France, Jul. 11-21, 2017) | Internal