Two-qubit quantum gates for defect qubits in diamond and similar systems

TL;DR

This paper introduces a fast, scalable all-optical method for implementing two-qubit gates in defect-based qubits like NV centers in diamond, utilizing microcavity photons and interference effects for high fidelity.

Contribution

It presents a novel all-optical design for two-qubit gates in defect qubits, leveraging microcavity photons and interference, with detailed quantum modeling demonstrating high-fidelity operations.

Findings

High-fidelity two-qubit gates achievable with realistic parameters.

All operations controlled by near-resonant optical pulses.

Cavity mode remains off-resonance during operations.

Abstract

We propose a fast, scalable all-optical design for arbitrary two-qubit operations for defect qubits in diamond (NV centers) and in silicon carbide, which are promising candidates for room temperature quantum computing. The interaction between qubits is carried out by microcavity photons. The approach uses constructive interference from higher energy excited states activated by optical control. In this approach the cavity mode remains off-resonance with the directly accessible optical transitions used for initialization and readout. All quantum operations are controlled by near-resonant narrow-bandwidth optical pulses. We perform full quantum numerical modeling of the proposed gates and show that high-fidelity operations can be obtained with realistic parameters.