Benchmark for Synthesized Diamond Sensors Based on Isotopically Engineered Nitrogen‐Vacancy Spin Ensembles for Magnetometry Applications

Abstract

Nitrogen‐vacancy (NV) center ensemble in synthetic diamond is a promising and emerging platform for quantum sensing technologies. Realization of such a solid‐state based quantum sensor is widely studied and requires reproducible manufacturing of NV centers with controlled spin properties, including the spin bath environment within the diamond crystal. Here, a non‐invasive method is reported to benchmark NV ensembles regarding their suitability as ultra‐sensitive magnetic field sensors. Imaging and electron spin resonance techniques are presented to determine operating figures and precisely define the optimal material for NV‐driven diamond engineering. The functionality of the methods is manifested on examples of chemical vapor deposition synthesized diamond layers containing preferentially aligned, isotopically controlled 15NV center ensembles. Quantification of the limiting 15N P1 spin bath, in an otherwise 12C enriched environment, and the reduction of its influence by applying dynamical decoupling protocols, complete the suggested set of criteria for the analysis of NV ensemble with potential use as magnetometers.

Optimizing ion implantation to create shallow NV centre ensembles in high-quality CVD diamond

“…The ESR lines have been fitted with a Lorentzian and the extracted linewidth is plotted in figure 7(b). The extracted linewidth is equal or better than values already reported in the litterature [21][22][23]. An almost linear relationship between PL intensity and linewidth is observed for count rates larger than 1.1 MHz with a similar trend for the regions implanted with 10 and 20 s of He + .…”

One decade of quantum optimal control in the chopped random basis

“…NV-centres in diamond form a highly advance platform for sensing and the contribution of QOC to these tasks has been highlighted in [39]. Furthermore, recent advances in diamond sample fabrication [190], and in control over a large number of spins associated with the NV centres [191,192], unlock new perspectives for the (d)CRAB method to rapidly assist and develop the realization of diamondbased quantum simulators and quantum registers. In the context of diamondbased quantum networks and quantum memories the (d)CRAB method is also straightforwardly applicable to other promising colour centres, such as silicon vacancy centres (SiV) [193], which is a good platform for studying energy efficient control at milli-Kelvin temperature and has a memory time exceeding 10 ms [194].…”

Enhancement of the creation yield of NV ensembles in a chemically vapour deposited diamond

“…In order to benchmark the grown material, we use the technique presented in [30]. The density of P1 bath spins is measured by using pulse sequence shown in Fig.…”

“…A few alternatives have been proposed to improve NV yield beyond that typically reached after growth. Recently, a creation yield close to 1/100 has for example been reported for specific growth conditions on a [111] orientation [30]. High energy electron or neutron irradiation may also be used to introduce additional vacancies in the diamonds and thus convert part of the nitrogen in the sample into useful NV centres [25,31].…”