Abstract Spin defects in solid-state materials are strong candidate systems for quantum information technology and sensing applications. Here we explore details the recently discovered negatively charged boron vacancies (V B − ) hexagonal nitride (hBN) demonstrate their use as atomic scale sensors temperature, magnetic fields externally applied pressure. These applications possible due to high-spin triplet ground state bright spin-dependent photoluminescence of V . Specifically, find that...

Atomic defects in 2D materials show excellent spin coherence time and become promising contenders for quantum applications.

Quantum systems can provide outstanding performance in various sensing applications, ranging from bioscience to nanotechnology. Atomic-scale defects silicon carbide are very attractive this respect because of the technological advantages material and favorable optical radio frequency spectral ranges control these defects. We identified several, separately addressable spin-3/2 centers same crystal, which immune nonaxial strain fluctuations. Some them characterized by nearly temperature...

Sensing magnetic fields is a key aspect in many areas of study such as biomedical imaging and geophysics. Researchers demonstrate all-optical solid-state magnetometry that sensitive to weaker than 100 nT.

Generation of single photons has been demonstrated in several systems. However, none them satisfies all the conditions, e.g. room temperature functionality, telecom wavelength operation, high efficiency, as required for practical applications. Here, we report fabrication light-emitting diodes (LEDs) based on intrinsic defects silicon carbide (SiC). To fabricate our devices used a standard semiconductor manufacturing technology combination with high-energy electron irradiation. The...

We report the realization of optically induced inverse population ground-state spin sublevels silicon vacancies ($V_{\mathrm{Si}}$) in carbide (SiC) at room temperature. The data show that probed vacancy ensemble can be prepared a coherent superposition states. Rabi nutations persist for more than 80 $\mu$s. Two opposite schemes optical alignment populations between upon illumination with unpolarized light are realized 4H- and 6H-SiC These altogether make SiC very favorable defect...

Abstract We report a giant thermal shift of 2.1 MHz/K related to the excited-state zero-field splitting in silicon vacancy centers 4H carbide. It is obtained from indirect observation optically detected magnetic resonance excited state using ground as an ancilla. Alternatively, relative variations for small temperature differences can be without application radiofrequency fields, by simply monitoring photoluminescence intensity vicinity level anticrossing. This effect results all-optical...

Quantum bit or qubit is a two-level system, which builds the foundation for quantum computation, simulation, communication and sensing. states of higher dimension, i.e., qutrits (D = 3) especially qudits 4 higher), offer significant advantages. Particularly, they can provide noise-resistant cryptography, simplify logic improve metrology. Flying solid-state have been implemented on basis photonic chips superconducting circuits, respectively. However, there still lack room-temperature with...

We generate silicon vacancy related defects in high-quality epitaxial carbide layers by means of electron irradiation. By controlling the irradiation fluence, defect concentration is varied over several orders magnitude. establish excitation profile for optical pumping these and evaluate optimum wavelength 770 nm. also measure photoluminescence dynamics at room temperature find a monoexponential decay with characteristic lifetime 6.1 ns. The integrated intensity depends linear on power...

Coherent coupling of defect spins with surrounding nuclei along the endowment to read out latter are basic requirements for an application in quantum technologies. We show that negatively charged boron vacancies (VB-) hexagonal nitride (hBN) meet these prerequisites. demonstrate Hahn-echo coherence VB- spin a characteristic decay time Tcoh = 15 μs, close theoretically predicted limit 18 μs defects hBN. Elongation up 36 is demonstrated by means Carr-Purcell-Meiboom-Gill decoupling technique....

We discovered uniaxial oriented centers in silicon carbide having unusual performance. Here we demonstrate that the family of silicon-vacancy related with $S= 3/2$ rhombic 15R-SiC crystalline matrix possess unique characteristics such as ODMR contrast and optical spin alignment existing at temperatures up to 250$^\circ$C. Thus concept optically addressable vacancy half integer ground state is extended wide class SiC polytypes. The structure these centers, which a fundamental problem for...

Bulk silicon carbide (SiC) is a very promising material system for bio-applications and quantum sensing. However, its optical activity lies beyond the near infrared spectral window in-vivo imaging fiber communications due to large forbidden energy gap. Here, we report fabrication of SiC nanocrystals isolation different nanocrystal fractions ranged from 600 nm down 60 in size. The structural analysis reveals further fragmentation smallest into ca. 10-nm-size clusters high crystalline quality,...

Optically addressable high-spin states (S ≥ 1) of defects in semiconductors are the basis for development solid-state quantum technologies. Recently, one such defect has been found hexagonal boron nitride (hBN) and identified as a negatively charged vacancy (VB−). To explore utilize properties this defect, needs to design robust way its creation an hBN crystal. We investigate possibility creating VB− centers single crystal by means irradiation with high-energy (E = 2 MeV) electron flux....

The research focuses on the explanation of a phenomenon observed in spectra electron nuclear resonance (ENDOR) pertaining to nitrogen atoms adjacent boron vacancy (VB) defect hexagonal nitride (hBN). is manifested as shift ENDOR spectrum lines with respect Larmor frequency. It hypothesized that these shifts are indicative substantial hyperfine interaction between VB and 14N nuclei hBN. A calculation utilizing second-order perturbation theory was executed determine positions lines, resulting...

The nitrogen-vacancy (NV) centers (NCVSi)− in 4H silicon carbide (SiC) constitute an ensemble of spin S = 1 solid state qubits interacting with the surrounding 14N and 29Si nuclei. As quantum applications based on a polarization transfer from electron to nuclei require knowledge electron–nuclear interaction parameters, we have used high-frequency (94 GHz) double resonance spectroscopy combined first-principles density functional theory investigate hyperfine nuclear quadrupole interactions...

Electron paramagnetic resonance (EPR) at 9.4 and 35 GHz were studied on two types of AlN single crystals, grown by a sublimation sandwich method. These investigations revealed the presence transition metals impurities in first sample: Fe2+ (S=2) some centers with S=3/2, we suggest Cr3+ or Ni3+ as possible candidates. The EPR spectra observed up to room temperature. After sample illumination 5 K light (wavelength shorter 700 nm) strong signal g factor shallow donors (SDs) slightly anisotropic...

The fine-structure splitting in zero magnetic field allows one to access the coherent control and manipulation of polarized spin states. Here zero-field (ZFS) $S=3/2$ silicon vacancy-related centers 6H-SiC is explored by means electron paramagnetic resonance nuclear double techniques, combined with first-principle calculations. We show that not only possess significantly different absolute values ZFS, but they also differ their sign. This diversity rationalized a flattened/elongated...

High-frequency pulsed electron paramagnetic resonance (EPR) and nuclear double (ENDOR) were used to determine interactions on remote ligand shells of silicon carbon in spin-3/2 color centers with an optically induced high-temperature spin alignment hexagonal $4H$-, $6H$-, rhombic $15R$-silicon carbide (SiC) polytypes. The EPR ENDOR experimental data relate unambiguously which the spin-level populations occurs. identification is based resolved hyperfine nearest, next-nearest, more distant...

Optically addressable spin-triplet defects in silicon carbide, such as divacancies and negatively charged nitrogen vacancy $({\mathrm{NV}}^{\ensuremath{-}})$ allow to develop modern quantum technologies operating the near-infrared range based on well-developed semiconductor material. Here, by means of both high-frequency (94 GHz) pulsed electron paramagnetic resonance (EPR) electron-nuclear double Rresonance (ENDOR) techniques ground state properties ${\mathrm{NV}}^{\ensuremath{-}}$ defect...

The negatively charged nitrogen-vacancy $({\mathrm{NV}}^{\ensuremath{-}})$ center in diamond is a promising candidate for many quantum applications. Here, we examine the splitting and broadening of center's infrared (IR) zero-phonon line (ZPL). We develop model these effects that accounts strain induced by photodependent microscopic distributions defects. apply this to interpret observed variations IR ZPL shape with temperature photoexcitation conditions. identify an anomalous...