Electric Dipole Induced Spin Resonance in Quantum Dots

TL;DR

This paper investigates how electric fields can control electron spins in quantum dots through spin-orbit interactions, identifying efficient mechanisms for spin manipulation relevant for quantum computing.

Contribution

It analyzes various spin-orbit couplings in quantum dots and derives an effective Hamiltonian for fast spin control using electric fields.

Findings

Linear Dresselhaus and Rashba couplings enable transverse magnetic fields for spin control.

Cubic Dresselhaus terms are effective in non-harmonic potentials.

Spin manipulation timescales of around 10 ns are achievable with current setups.

Abstract

An alternating electric field, applied to a quantum dot, couples to the electron spin via the spin-orbit interaction. We analyze different types of spin-orbit coupling known in the literature and find two efficient mechanisms of spin control in quantum dots. The linear in momentum Dresselhaus and Rashba spin-orbit couplings give rise to a fully transverse effective magnetic field in the presence of a Zeeman splitting at lowest order in the spin-orbit interaction. The cubic in momentum Dresselhaus terms are efficient in a quantum dot with non-harmonic confining potential and give rise to a spin-electric coupling proportional to the orbital magnetic field. We derive an effective spin Hamiltonian, which can be used to implement spin manipulation on a timescale of $10 {\rm ns}$ with the current experimental setups.