Fast High-Fidelity Hole Spin Initialisation in a Single Quantum Dot at Zero Magnetic Field

Abstract

Fast (∼50 ps) initialization of a long-lived hole spin qubit in a single InGaAs quantum dot is achieved by exciton ionization. A QD exhibiting no fine structure yields fidelities exceeding 98% at zero external field thus forming a key building block for high fidelity quantum information processing.