On Feedback Control Algorithms for Nitrogen-Vacancy Quantum Sensing

Abstract

Ultrasensitive quantum detection of external weak signals at the nanoscale levels can be implemented in a variety of forms. Here we discuss different feedback control algorithms for the sensing scenario based on the semiclassical Tavis-Cummings model for nitrogen-vacancy (NV) centers located in the diamond. In the frame of this model, the sensing elements are considered as non-interacting two-level quantum systems, distributed in-homogeneously due to heterogeneous local magnetic and strain environments. The dynamical system of ordinary differential equations corresponding to the model contains the set of control parameters: the detunings between the drive frequency and the cavity frequency and between the drive frequency and NV transition frequency, as well as the relaxation coefficients. Correspondingly, it opens a gate for developing feedback control algorithms for tracking the cavity field, the income signal, and the reflection signal in the model sensing system. To study the principal features of algorithmic feedback we formulate the simplified ’toy model’ for the TavisCummings system and investigate alternative schemes of feedback (gradient methods, target attractor methods) to compare their pros and cons for effective control for nitrogen-vacancy-cavity quantum sensing based on different choices of the control parameter set. This work was supported by the Research Fund of Abdullah Gül University; Project Number: BAP FBA-2023-176 ’Geribesleme kontrol algoritmaları ile kubit tabanlı sensörlerin verimliliğinin artırılması’. The paper was presented at PhysCon2024. © 2024 Elsevier B.V., All rights reserved.