Designed defects in 2D antidot lattices for quantum information processing

TL;DR

This paper introduces a novel approach to quantum information processing using defect states in 2D antidot lattices, demonstrating localized states and feasible spin qubit implementation in semiconductor heterostructures.

Contribution

It proposes a new physical realization of spin qubits via defect states in antidot lattices, with detailed band structure calculations and exchange coupling analysis.

Findings

Localized defect states form within the antidot lattice.

The energy structure of defect states is robust against thermal dephasing.

Exchange coupling between defect states is similar to double quantum dots.

Abstract

We propose a new physical implementation of spin qubits for quantum information processing, namely defect states in antidot lattices defined in the two-dimensional electron gas at a semiconductor heterostructure. Calculations of the band structure of a periodic antidot lattice are presented. A point defect is created by removing a single antidot, and calculations show that localized states form within the defect, with an energy structure which is robust against thermal dephasing. The exchange coupling between two electrons residing in two tunnel-coupled defect states is calculated numerically. We find results reminiscent of double quantum dot structures, indicating that the suggested structure is a feasible physical implementation of spin qubits.