arXiv subjects

V. N. Sorokin

Publications and source records attributed to V. N. Sorokin.

12 recordsLinked to original sources

arXiv2025

Bichromatic microwave manipulation of the NV center nuclear spin using transition not detectable via optically detected magnetic resonance

Recently, rotation sensors utilizing the nuclear spins of nitrogen-vacancy color centers in diamond have been demonstrated. However, these devices are power-intensive and challenging to integrate into small chip-based radiofrequency antennas and circuits necessary for controlling nuclear spins or producing relatively high magnetic fields. To address this issue, the coherent manipulation of nuclear spins via coherent population trapping at moderate magnetic fields using microwave fields has been successfully demonstrated in isotopically pure diamond. In this work, we demonstrate that a similar technique can be applied to a diamond plate with a natural abundance of carbon-13, which holds significant potential for practical sensing applications. Although the forbidden resonances required for coherent control were only partially observed, coherent population trapping was successfully demonstrated at both visible and invisible transitions, with an apparent contrast of up to 98+-11% and a true contrast of approximately 35+-7%. This finding confirms the feasibility of coherent nuclear spin control even in diamond plates with naturally occurring carbon-13

quant-ph↗

arXiv2024

Optimization of the sensitivity of a temperature sensor based on germanium-vacancy color center (GeV) in diamond

Temperature sensors based on the GeV color center in diamond are gaining considerable attention in both scientific and industrial fields. For widespread industrial adoption, however, these sensors need a design that is as simple and cost-effective as possible. The original sensor design relied on measuring the spectral characteristics of the zero-phonon line. Recently, a modified approach was introduced, which involves splitting the GeV emission with a dichroic mirror and determining temperature based on the ratio of the two resulting signals. In this analysis, we provide a detailed comparison of both methods. At room temperature, the two methods show comparable performance, with slight variations depending on component quality. However, at temperatures around 300 °C, the new method's performance is estimated to be nearly twice that of the original, provided optimal filter parameters are used. Additionally, the sensitivity of the new method remains roughly consistent with its performance at room temperature.

physics.ins-det↗

arXiv2023

Interaction of Nitrogen-Vacancy Centers in Diamond with a Dense Ensemble of Carbon-13

The nitrogen-vacancy center in diamond attracts a lot of attention in sensing applications, mainly for temperature, magnetic field, and rotation measurements. Nuclear spins of carbon-13 surrounding the nitrogen-vacancy center can be used as a memory or sensing element. In the current work, a diamond plate with a relatively large concentration of carbon-13 was synthesized and examined. The spectrum of optically detected magnetic resonance was recorded and analyzed in a magnetic field range of 5-200 G. A strain-independent measurement technique of carbon-13 isotope concentration based on the analysis of magnetic resonance spectra was developed. Additionally, narrow features in the spectrum were detected and understood.

quant-ph↗

arXiv2022

Optimal microwave control pulse for nuclear spin polarization and readout in dense nitrogen-vacancy ensembles in diamond

Nitrogen-vacancy centers possessing nuclear spins are promising candidates for a novel nuclear spin gyroscope. Preparation of a nuclear spin state is a crucial step to implement a sensor that utilizes a nuclear spin. In a low magnetic field, such a preparation utilizes population transfer, from polarized electronic spin to nuclear spin, using microwave pulses. The use of the narrowband microwave pulse proposed earlier is inefficient when magnetic transitions are not well resolved, particularly when applied to diamond with a natural abundance of carbon atoms or dense ensembles of nitrogen-vacancy centers. In this study, the authors performed optimization of the pulse shape for 3 relatively easily accessible pulse shapes. The optimization was done for a range of magnetic transition linewidths, corresponding to the practically important range of nitrogen concentrations (5-50 ppm). It was found that, while at low nitrogen concentrations, optimized pulse added very little to simple square shape pulse, and in the case of dense nitrogen-vacancy ensembles, with a rather wide magnetic transition width of 1.5 MHz optimal pulses, a factor of 15% improvement in the population of the target state was observed.

quant-ph↗

arXiv2022

The study of the efficiency of nitrogen to NV-center conversion in high nitrogen content samples

The nitrogen-vacancy color center in diamond is one of the most important systems in the fast-growing field of sensing. This color centers are used in both high-resolution and high-sensitivity sensors. However, techniques for quick and efficient formations of this color center are still in the development stage. In this paper, we present a study on the influence of the electron irradiation dose on the conversion of substitutional nitrogen into $\text{N}{\text{V}^{-}}$ centers. The study was done on diamonds that were highly enriched with nitrogen (~100 ppm), which on one hand should maximize the effect of irradiation, and on another be of interest for high-sensitivity magnetometers. The maximum achieved conversion efficiency was as high as ${37\pm 3.7}$, with no observed saturation on the electron dose even with the simplest annealing procedure. The measurements of the corresponding dephasing time made it possible to estimate for shot-noise limited sensitivity per unit volume of a stationary field sensor with such a diamond to be ${9\pm 1\times {{10}^{-14}}\text{T}}/{\sqrt{\text{Hz}\cdot \text{m}{\text{m}^{-3}}}}\;$.

cond-mat.mtrl-sci↗

arXiv2020

Optimization of the coherence properties of diamond samples with an intermediate concentration of NV centers

The sensitivity of the nitrogen-vacancy (NV) color centers in diamond-based magnetometers strongly depends on the number of NV centers involved in the measurement. Unfortunately, an increasing concentration of NV centers leads to decreases of their dephasing and coherence time if the nitrogen content exceeds a certain threshold level (approximately ${10^{17}}{\rm{ c}}{\rm{m}^{ - 3}}$). Here, we demonstrate that this increased dephasing can be efficiently compensated by postprocessing procedures in the vicinity of the threshold concertation, thus extending possible useful concentrations on NV centers with the maximum possible decoherence time in diamonds with a natural carbon content.

physics.app-ph↗

arXiv2018

Spin properties of NV centers in high-pressure, high-temperature grown diamond

The sensitivity of magnetic and electric field sensors based on nitrogen-vacancy (NV) center in diamond strongly depends on the available concentration of NV and their coherence properties. Achieving high coherence times simultaneously with high concentration is a challenging experimental task. Here, we demonstrate that by using a high-pressure, high-temperature growing technique, one can achieve nearly maximally possible effective coherence T2* times, limited only by carbon nuclear spins at low nitrogen concentrations or nitrogen electron spin at high nitrogen concentrations. Hahn-echo T2 coherence times were also investigated and found to demonstrate reasonable values. Thus, the high-pressure, high-temperature technique is a strong contender to the popular chemical vapor deposition method in the development of high-sensitivity, diamond-based sensors.

physics.app-ph↗

arXiv2018

Temperature drift rate for nuclear terms of NV center ground state Hamiltonian

Nitrogen-vacancy (NV) center in diamond was found to be a powerful tool for various sensing applications. The main work horse of this center so far has been optically detected electron resonance. Utilization of the nuclear spin has the potential of significantly improving sensitivity in rotation and magnetic field sensors. Ensemble-based sensors consume quite a bit of power, thus requiring an understanding of temperature-related shifts. In this article, we provide a detailed study of the temperature shift of the hyperfine components of the NV center.

physics.atom-ph↗

arXiv2018

Polarized cold cloud of thulium atom

Minimization of internal degrees of freedom is an important step in the cooling of atomic species to degeneracy temperature. Here, we report on the loading of 6*10^5 thulium atoms optically polarized at maximum possible magnetic quantum number mf=-4 state into dipole trap operating at 532 nm. The purity of polarizations of the atoms was experimentally verified using a Stern-Gerlach-type experiment. Experimental measured polarization of the state is 3.91(26).

physics.atom-ph↗

arXiv2016

Superconducting detector for visible and near-infrared quantum emitters

Further development of quantum emitter based communication and sensing applications intrinsically depends on the availability of robust single-photon detectors. Here, we demonstrate a new generation of superconducting single-photon detectors specifically optimized for the 500-1100 nm wavelength range, which overlaps with the emission spectrum of many interesting solid-state atom-like systems, such as nitrogen-vacancy and silicon-vacancy centers in diamond. The fabricated detectors have a wide dynamic range (up to 350 million counts per second), low dark count rate (down to 0.1 counts per second), excellent jitter (62 ps), and the possibility of on-chip integration with a quantum emitter. In addition to performance characterization, we tested the detectors in real experimental conditions involving nanodiamond nitrogen-vacancy emitters enhanced by a hyperbolic metamaterial.

quant-ph↗

arXiv2016

Improved measurement of the hyperfine structure of the laser cooling level $4f^{12}(^3 H_6)5d_{5/2}6s^2$ $(J=9/2)$ in $^{169}$Tm

We report on the improved measurement of the hyperfine structure of $4f^{12}(^3 H_6)5d_{5/2}6s^2$ $(J=9/2)$ excited state in Tm-169 which is involved in the second-stage laser cooling of Tm. To measure the absolute value of the hyperfine splitting interval we used Doppler-free frequency modulation saturated absorption spectroscopy of Tm atoms in a vapor cell. The sign of the hyperfine constant was determined independently by spectroscopy of laser cooled Tm atoms. The hyperfine constant of the level equals $A_J=-422.112(32)$ MHz that corresponds to the energy difference between two hyperfine sublevels of $-2110.56(16)$~MHz. In relation to the saturated absorption measurement we quantitatively treat contributions of various mechanisms into the line broadening and shift. We consider power broadening in the case when Zeeman sublevels of atomic levels are taken into account. We also discuss the line broadening due to frequency modulation and relative intensities of transitions in saturated-absorption experiments.

physics.atom-ph↗

arXiv2008

Mixed type multiple orthogonal polynomials for two Nikishin systems

We study the logarithmic and ratio asymptotic of linear forms constructed from a Nikishin system which satisfy orthogonality conditions with respect to a system of measures generated from another Nikishin system. This construction combines type I and type II multiple orthogonal polynomials. The logarithmic asymptotic of the linear forms is expressed in terms of the extremal solution of an associated vector valued equilibrium problem for the logarithmic potential. The ratio asymptotic is described by means of a conformal representation of an appropriate Riemann surface of genus zero onto the extended complex plane.

math.CV↗