Quantum control-enhanced sensing and spectroscopy with NV qubits in diamond
Authors: Hernández-Gómez S., Poggiali F., Cappellaro P., Fabbri N.,
Autors Affiliation: European Laboratory for Non-linear Spectroscopy and Dept. of Physics, Univ. degli Studi di Firenze, I-50019 Sesto Fiorentino, Italy;
CNR-INO Istituto Nazionale di Ottica del Consiglio Nazionale delle Ricerche, I-50019 Sesto Fiorentino, Italy;
Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139
Abstract: Quantum sensors take advantage of the inherent sensitivity of quantum systems to external environment perturbations to precisely measure target signals. The same interaction with the environment, however, limits the device sensitivity by reducing the coherence of the quantum states. Quantum control can play a crucial role in improving the sensor performance. We explore quantum control tools to improve the performance of a Nitrogen-Vacancy (NV) center as a single-qubit sensor of ultra-weak magnetic fields in noisy environments. We present a method to obtain a precise spectroscopic characterization of the NV environment, instrumental to design robust sensing strategies with improved noise protection. Then, we exploit optimal quantum control | based on a set of numerical methods to optimize the temporal dependence of the sensor driving field | adapted to quantum sensing purposes, and prove its advantage to achieve best compromises between signal acquisition and noise cancellation.
KeyWords: NV centers in diamond, quantum devices, quantum sensors, quantum control, noise spectroscopy