Detection of Angular Momentum Transfer from a Single Photon to a Single Electron Spin in a Lateral Double Quantum Dot

高史藤田

Published Mar 24, 2014• 0 citations

Abstract

The information transfer from a photon to an electron spin in semiconductors is predicted to forward the realization of quantum computation.Gate defined lateral quantum dots is an attractive platform in this sense since the electrical single and two quantum bit (qubit) gate operations have been demonstrated only in this system.However, realization of quantum media conversion is limited up to the single photon to charge conversion due to the large disturbance of electrostatic potentials by the irradiation of light.It is still challenging to achieve high visibility of single-shot photoelectron spin measurements and the detection of angular momentum transfer from a single photon polarization to a single photoelectron spin.This work presents the detection of single photoelectron spins excited by single circularly polarized photons and confirm the optical selection rules associated with the conversion.Double heterostructure GaAs quantum wells (QWs) were prepared to selectively excite electron spins from the discrete heavy and light hole bands.The QWs are also designed to meet the requirement of the coherent transfer scheme.The out of plane electron g-factors were measured from resistively detected electron spin resonance experiments and we determined the well width implying the near zero in-plane electron g-factor.To overcome the disturbance due to light irradiation, a double quantum dot (DQD) was formed on the chosen QW.DQDs are preferable for high visibility detection of spin states using Pauli spin blockade.Additionally, under i Here, I would like to thank them all.

DOI: 10.15083/00006774

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