Local vibrational modes of Si vacancy spin qubits in SiC
- URL: http://arxiv.org/abs/2002.00067v2
- Date: Tue, 4 Feb 2020 20:18:17 GMT
- Title: Local vibrational modes of Si vacancy spin qubits in SiC
- Authors: Z. Shang, A. Hashemi, Y. Berenc\'en, H.-P. Komsa, P. Erhart, A. V.
Krasheninnikov, G. V. Astakhov
- Abstract summary: We uncover the local vibrational modes of the Si vacancy spin qubits in as-grown 4H-SiC.
Our findings give insight into the coupling of electronic states to vibrational modes in SiC spin qubits.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Silicon carbide is a very promising platform for quantum applications because
of extraordinary spin and optical properties of point defects in this
technologically-friendly material. These properties are strongly influenced by
crystal vibrations, but the exact relationship between them and the behavior of
spin qubits is not fully investigated. We uncover the local vibrational modes
of the Si vacancy spin qubits in as-grown 4H-SiC. We apply the resonant
microwave field to isolate the contribution from one particular type of
defects, the so-called V2 center, and observe the zero-phonon line together
with seven equally-separated phonon replicas. Furthermore, we present
first-principles calculations of the photoluminescence lineshape, which are in
excellent agreement with our experimental data. To boost up the calculation
accuracy and decrease the computation time, we extract the force constants
using machine learning algorithms. This allows us to identify dominant modes in
the lattice vibrations coupled to an excited electron during optical emission
in the Si vacancy. The resonance phonon energy of 36 meV and the Debye-Waller
factor of about 6% are obtained. We establish experimentally that the
activation energy of the optically-induced spin polarization is given by the
local vibrational energy. Our findings give insight into the coupling of
electronic states to vibrational modes in SiC spin qubits, which is essential
to predict their spin, optical, mechanical and thermal properties. The approach
described can be applied to a large variety of spin defects with spectrally
overlapped contributions in SiC as well as in other 3D and 2D materials.
Related papers
- Quantum Vibronic Effects on the Excitation Energies of the
Nitrogen-Vacancy Center in Diamond [0.0]
We investigate the impact of quantum vibronic coupling on the electronic properties of solid-state spin defects using methods and first principles molecular dynamics with a quantum thermostat.
We found a significant dynamic Jahn-Teller splitting of the doubly degenerate single-particle levels within the diamond's band gap, even at 0 K, with a magnitude exceeding 180 meV.
arXiv Detail & Related papers (2024-01-12T18:30:29Z) - Spin-phonon decoherence in solid-state paramagnetic defects from first
principles [79.4957965474334]
Paramagnetic defects in diamond and hexagonal boron nitride possess a unique combination of spin and optical properties that make them solid-state qubits.
Despite the coherence of these spin qubits being critically limited by spin-phonon relaxation, a full understanding of this process is not yet available.
We demonstrate that low-frequency two-phonon modulations of the zero-field splitting are responsible for spin relaxation and decoherence.
arXiv Detail & Related papers (2022-12-22T13:48:05Z) - Identification of acoustically induced spin resonances of Si vacancy
centers in 4H-SiC [0.0]
We show that the dynamic strain of surface acoustic waves can overcome the limitation of spin control above cryogenic temperatures.
The acoustic spin control of both kinds of $mathrmV_mathrmSi$ centers in their excited states opens new ways for applications in quantum technologies based on spin-optomechanics.
arXiv Detail & Related papers (2022-12-15T10:27:38Z) - Probing dynamics of a two-dimensional dipolar spin ensemble using single
qubit sensor [62.997667081978825]
We experimentally investigate individual spin dynamics in a two-dimensional ensemble of electron spins on the surface of a diamond crystal.
We show that this anomalously slow relaxation rate is due to the presence of strong dynamical disorder.
Our work paves the way towards microscopic study and control of quantum thermalization in strongly interacting disordered spin ensembles.
arXiv Detail & Related papers (2022-07-21T18:00:17Z) - Spin-optical dynamics and quantum efficiency of single V1 center in
silicon carbide [1.6492256668939613]
We study the spin-optical dynamics of single silicon vacancy center at hexagonal lattice sites, namely V1, in 4H-polytype silicon carbide.
By utilizing resonant and above-resonant sub-lifetime pulsed excitation, we determine spin-dependent excited-state lifetimes and intersystem-crossing rates.
arXiv Detail & Related papers (2022-03-15T18:12:17Z) - Visualizing spinon Fermi surfaces with time-dependent spectroscopy [62.997667081978825]
We propose applying time-dependent photo-emission spectroscopy, an established tool in solid state systems, in cold atom quantum simulators.
We show in exact diagonalization simulations of the one-dimensional $t-J$ model that the spinons start to populate previously unoccupied states in an effective band structure.
The dependence of the spectral function on the time after the pump pulse reveals collective interactions among spinons.
arXiv Detail & Related papers (2021-05-27T18:00:02Z) - Light-matter interactions near photonic Weyl points [68.8204255655161]
Weyl photons appear when two three-dimensional photonic bands with linear dispersion are degenerated at a single momentum point, labeled as Weyl point.
We analyze the dynamics of a single quantum emitter coupled to a Weyl photonic bath as a function of its detuning with respect to the Weyl point.
arXiv Detail & Related papers (2020-12-23T18:51:13Z) - Room Temperature Coherent Control of Spin Defects in hexagonal Boron
Nitride [0.0]
Optically active defects in solids with accessible spin states are promising candidates for solid state quantum information and sensing applications.
We realize coherent control of ensembles of boron vacancy centers in hexagonal boron nitride (hBN)
Our results are important for employment of van der Waals materials for quantum technologies.
arXiv Detail & Related papers (2020-10-23T16:31:37Z) - A multiconfigurational study of the negatively charged nitrogen-vacancy
center in diamond [55.58269472099399]
Deep defects in wide band gap semiconductors have emerged as leading qubit candidates for realizing quantum sensing and information applications.
Here we show that unlike single-particle treatments, the multiconfigurational quantum chemistry methods, traditionally reserved for atoms/molecules, accurately describe the many-body characteristics of the electronic states of these defect centers.
arXiv Detail & Related papers (2020-08-24T01:49:54Z) - Optical spin initialization of spin-3/2 silicon vacancy centers in
6H-SiC at room temperature [0.6719751155411073]
We study the optical alignment of the spin 3/2 negatively charged silicon vacancy in 6H-SiC.
We describe a simple rate equation model that can explain the observed behaviour.
arXiv Detail & Related papers (2020-07-14T18:04:14Z) - Effect of phonons on the electron spin resonance absorption spectrum [62.997667081978825]
We model the effect of phonons and temperature on the electron spin resonance (ESR) signal in magnetically active systems.
We find that the suppression of ESR signals is due to phonon broadening but not based on the common assumption of orbital quenching.
arXiv Detail & Related papers (2020-04-22T01:13:07Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.