Fast Arbitrary Qutrit Gates for NV Centers in the Low-Field Regime

TL;DR

This paper introduces a method for implementing fast, arbitrary three-level quantum gates (qutrit gates) in NV centers using monochromatic microwave pulses, enabling advanced quantum control in low magnetic fields.

Contribution

It presents a novel scheme for realizing universal SU(3) operations on NV center qutrits by extending SU(2) control techniques to the full three-level system.

Findings

Demonstrates decomposition of SU(3) operations into simpler rotations.

Shows implementation of quantum state tomography for three-level systems.

Achieves fast, arbitrary qutrit gates in NV centers.

Abstract

The ground state of the negatively charged NV center forms a spin-1 manifold providing a versatile platform for sensing and information processing. Here we present a scheme for implementing fast arbitrary qutrit gates in the low-field regime using monochromatic microwave pulses of constant intensity tuned to the zero-field transition. By concatenating pulses with appropriate phases and durations, the NV-ERC scheme is extended from SU(2) operations in the double-quantum subspace to the full three-level structure. We show that arbitrary SU(3) operations can be decomposed into rotations in the double-quantum subspace together with effective implementations of the generators related to $\hat{\lambda}_5$ and $\hat{\lambda}_8$. We illustrate this decomposition with a use case: performing quantum state tomography of the complete three-level density matrix.