Zeno Quantum Gates in Semiconductor Quantum Dots

TL;DR

This paper introduces a scheme for implementing a two-qubit conditional phase gate in semiconductor quantum dots using the quantum Zeno effect, with improved fidelity through phonon-assisted relaxation.

Contribution

It presents a novel quantum gate scheme leveraging phonon-assisted relaxation and the quantum Zeno effect in semiconductor quantum dots, with analytical solutions and realistic simulations.

Findings

Larger phonon relaxation rates enhance gate fidelity.

The scheme achieves high-fidelity two-qubit operations.

Analytical master equation solutions support the approach.

Abstract

We propose a scheme for a two-qubit conditional phase gate by quantum Zeno effect with semiconductor quantum dots. The system consists of two charged dots and one ancillary dot that can perform Rabi oscillations under a resonant laser pulse. The quantum Zeno effect is induced by phonon-assisted exciton relaxation between the ancillary dot and the charged dots, which is equivalent to a continuous measurement. We solve analytically the master equation and simulate the dynamics of the system using a realistic set of parameters. In contrast to standard schemes, larger phonon relaxation rates increase the fidelity of the operations.