Coherent single electron spin control in a slanting Zeeman field

TL;DR

This paper proposes a method for coherent control of a single electron spin in a quantum dot using a static slanting Zeeman field, enabling quantum gate operations without external magnetic fields.

Contribution

It introduces a novel scheme for manipulating electron spin qubits via voltage control in a static magnetic field gradient, avoiding the need for dynamic magnetic fields or spin-orbit coupling.

Findings

Demonstrates coherent single-qubit rotations and C-NOT gate feasibility.

Estimates relaxation and coherence times for the proposed scheme.

Shows experimental advantages of static field-based spin control.

Abstract

We consider a single electron in a 1D quantum dot with a static slanting Zeeman field. By combining the spin and orbital degrees of freedom of the electron, an effective quantum two-level (qubit) system is defined. This pseudo-spin can be coherently manipulated by the voltage applied to the gate electrodes, without the need for an external time-dependent magnetic field or spin-orbit coupling. Single qubit rotations and the C-NOT operation can be realized. We estimated relaxation ($T_1$) and coherence ($T_{2}$) times, and the (tunable) quality factor. This scheme implies important experimental advantages for single electron spin control.