Probing the coherence of solid-state qubits at avoided crossings

Abstract

Optically addressable paramagnetic defects in wide-band-gap semiconductors are promising platforms for quantum communications and sensing. The presence of avoided crossings between the electronic levels of these defects can substantially alter their quantum dynamics and be both detrimental and beneficial for quantum information applications. Avoided crossings give rise to clock transitions, which can significantly improve protection from magnetic noise and favorably increase coherence time. However, the reduced coupling between electronic and nuclear spins at an avoided crossing may be detrimental to applications where nuclear spins act as quantum memories. Here we present a combined theoretical and experimental study of the quantum dynamics of paramagnetic defects interacting with a nuclear spin bath at avoided crossings. We develop a computational approach based on a generalization of the cluster expansion technique, which can account for processes beyond pure dephasing and describe the dynamics of any solid-state spin-qubits near avoided crossings. Using this approach and experimental validation, we determine the change in nature and source of noise at avoided crossings for divacancies in SiC. We find that we can condition the clock transition of the divacancies in SiC on multiple adjacent nuclear spins states. In our experiments, we demonstrate that one can suppress the effects of fluctuating charge impurities with depletion techniques, leading to an increased coherence time at clock transition, limited purely by magnetic noise. Combined with ab-initio predictions of spin Hamiltonian parameters, the proposed theoretical approach paves the way to designing the coherence properties of spin qubits from first principles.

arXiv comment29 pages, 7 figures

References in corpus (45)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Quantum sensing
• Electron spin relaxation by nuclei in semiconductor quantum dots
• Quantum computing with defects
• Universal dynamical decoupling of a single solid-state spin from a spin bath
• High-fidelity projective readout of a solid-state spin quantum register
• Electron spin coherence exceeding seconds in high purity silicon
• Isolated electron spins in silicon carbide with millisecond-coherence times
• Temperature and magnetic field dependent longitudinal spin relaxation in nitrogen-vacancy ensembles in diamond
• Polytype control of spin qubits in silicon carbide
• Decoherence-protected quantum gates for a hybrid solid-state spin register
• One-second coherence for a single electron spin coupled to a multi-qubit nuclear-spin environment
• Atomic clock transitions in silicon-based spin qubits
• Quantum theory for electron spin decoherence induced by nuclear spin dynamics in semiconductor quantum computer architectures: Spectral diffusion of localized electron spins in the nuclear solid-state environment
• Electrical and optical control of single spins integrated in scalable semiconductor devices
• Probing spin-phonon interactions in silicon carbide with Gaussian acoustics
• Decoherence and dynamical decoupling control of nitrogen-vacancy center electron spins in nuclear spin baths
• Quantum decoherence dynamics of divacancy spins in silicon carbide
• Electrically and mechanically tunable electron spins in silicon carbide color centers
• Quantum many-body theory of qubit decoherence in a finite-size spin bath
• Entanglement and control of single quantum memories in isotopically engineered silicon carbide
• Optical charge state control of spin defects in 4H-SiC
• Purcell enhancement of a single silicon carbide color center with coherent spin control
• Quantum many-body theory for electron spin decoherence in nanoscale nuclear spin baths
• Universal coherence protection in a solid-state spin qubit
• Competition between electric field and magnetic field noise in the decoherence of a single spin in diamond
• High resolution spectroscopy of single NV defects coupled with nearby ${}^{13}$C nuclear spins in diamond
• Robust quantum-network memory using decoherence-protected subspaces of nuclear spins
• Electron Spin Decoherence in Silicon Carbide Nuclear Spin Bath
• Quantum Decoherence of the Central Spin in a Sparse System of Dipolar Coupled Spins
• Observation of anomalous decoherence effect in a quantum bath at room temperature
• Electrically driven optical interferometry with spins in silicon carbide
• Coherent spin control by electrical manipulation of the magnetic anisotropy
• Bismuth in silicon qubits: the role of EPR cancellation resonances
• Uncovering many-body correlations in nanoscale nuclear spin baths by central spin decoherence
• Efficient quantum gates for individual nuclear spin qubits by indirect control
• Quantum bath-driven decoherence of mixed spin systems
• From quantum-mechanical to classical dynamics in the central-spin model
• When can quantum decoherence be mimicked by classical noise?
• Longitudinal spin relaxation model applied to point defect qubit systems
• The classical nature of nuclear spin noise near clock transitions of Bi donors in silicon
• Longitudinal relaxation of a nitrogen-vacancy center in a spin bath by generalized cluster-correlation expansion method
• Cluster-correlation expansion for studying decoherence of clock transitions in spin baths
• Keeping a spin qubit alive in natural silicon: Comparing optimal working points and dynamical decoupling
• Strong polarization of individual nuclear spins weakly coupled to nitrogen-vacancy color centers in diamond

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• Substrate-controlled dynamics of spin qubits in low dimensional van-der-Waals materials
• High Frequency Magnetometry with an Ensemble of Spin Qubits in Hexagonal Boron Nitride
• Decoherence of Nuclear Spins in the Proximity of Nitrogen Vacancy Centers in Diamond
• Performance of quantum registers in diamond in the presence of spin impurities
• Spin coherence in strongly coupled spin baths in quasi-two-dimensional layers
• Stability and decoherence analysis of the silicon vacancy in 3C-SiC
• Coherence properties of NV-center ensembles in diamond coupled to an electron-spin bath
• Magnetic-field dependent VB- spin decoherence in hexagonal boron nitrides: A first-principles study
• Understanding Decoherence of the Boron Vacancy Center in Hexagonal Boron Nitride
• Towards dislocation-driven quantum interconnects
• Wavelet-resolved coherence beats in the Overhauser field of a thermal nuclear spin ensemble
• First-principles computational methods for quantum defects in two-dimensional materials: A perspective
• Maximizing information obtainable by quantum sensors through the Quantum Zeno Effect
• Wavelet-based Ramsey magnetometry enhancement of a single NV center in diamond
• Sudden death of entanglement with Hamiltonian ensemble assisted by auxiliary qubits
• Quantum decoherence of nitrogen-vacancy spin ensembles in a nitrogen spin bath in diamond under dynamical decoupling
• Enhancing Coherence with a Clock Transition and Dynamical Decoupling in the Cr${}_7$Mn Molecular Nanomagnet
• Numerically exact quantum dynamics with tensor networks: Predicting the decoherence of interacting spin systems
• Simulating decoherence of two coupled spins using the generalized cluster correlation expansion
• Decoherence of V${}_{\mathrm{B}}^{-}$ spin defects in monoisotopic hexagonal boron nitride