Optical control of one and two hole spins in interacting quantum dots

TL;DR

This paper demonstrates fast optical control of single and coupled hole spins in quantum dots, highlighting their potential for scalable quantum information processing due to reduced hyperfine interactions.

Contribution

It introduces a method for fast optical manipulation of single and two-hole spins in coupled quantum dots, advancing quantum dot qubit scalability.

Findings

Achieved fast single-qubit gates with laser pulses.

Demonstrated optical control of two interacting hole spins.

Showed potential for scalable quantum information processing.

Abstract

A single hole spin in a semiconductor quantum dot has emerged as a quantum bit that is potentially superior to an electron spin. A key feature of holes is that they have a greatly reduced hyperfine interaction with nuclear spins, which is one of the biggest difficulties in working with an electron spin. It is now essential to show that holes are viable for quantum information processing by demonstrating fast quantum gates and scalability. To this end we have developed InAs/GaAs quantum dots coupled through coherent tunneling and charged with controlled numbers of holes. We report fast, single qubit gates using a sequence of short laser pulses. We then take the important next step toward scalability of quantum information by optically controlling two interacting hole spins in separate dots.