Coherent transfer of light polarization to electron spins in a semiconductor

TL;DR

This paper demonstrates a method to coherently transfer the superposition of light polarization states to electron spins in a semiconductor, enabling potential quantum information transfer between photons and spins.

Contribution

It introduces a technique to transfer light polarization superpositions to electron spins in semiconductors, overcoming electron-hole entanglement issues.

Findings

Coherent transfer of light polarization to electron spins demonstrated.

Time-resolved Kerr rotation used to observe spin precession.

Breaks electron-hole entanglement via g-factor discrepancy.

Abstract

We demonstrate that the superposition of light polarization states is coherently transferred to electron spins in a semiconductor quantum well. By using time-resolved Kerr rotation we observe the initial phase of Larmor precession of electron spins whose coherence is transferred from light. To break the electron-hole spin entanglement, we utilized the big discrepancy between the transverse g-factors of electrons and light holes. The result encourages us to make a quantum media converter between flying photon qubits and stationary electron spin qubits in semiconductors.