Electron spin relaxations of phosphorus donors in bulk silicon under large electric field

Abstract

Modulation of donor electron wavefunction via electric fields is vital to quantum computing architectures based on donor spins in silicon. For practical and scalable applications, the donor-based qubits must retain sufficiently long coherence times in any realistic experimental conditions. Here, we present pulsed electron spin resonance studies on the longitudinal $(T_1)$ and transverse $(T_2)$ relaxation times of phosphorus donors in bulk silicon with various electric field strengths up to near avalanche breakdown in high magnetic fields of about 1.2 T and low temperatures of about 8 K. We find that the $T_1$ relaxation time is significantly reduced under large electric fields due to electric current, and $T_2$ is affected as the $T_1$ process can dominate decoherence. Furthermore, we show that the magnetoresistance effect in silicon can be exploited as a means to combat the reduction in the coherence times. While qubit coherence times must be much longer than quantum gate times, electrically accelerated $T_1$ can be found useful when qubit state initialization relies on thermal equilibration.

arXiv comment7 pages, 5 figures

References in corpus (14)

• A single-atom electron spin qubit in silicon
• Single-shot readout of an electron spin in silicon
• Electron spin coherence exceeding seconds in high purity silicon
• Storing quantum information for 30 seconds in a nanoelectronic device
• High-fidelity readout and control of a nuclear spin qubit in silicon
• Electron Spin-Relaxation Times of Phosphorus Donors in Silicon
• Silicon quantum processor with robust long-distance qubit couplings
• Quantifying the quantum gate fidelity of single-atom spin qubits in silicon by randomized benchmarking
• Line Broadening and Decoherence of Electron Spins in Phosphorus-Doped Silicon Due to Environmental 29^Si Nuclear Spins
• A silicon-based surface code quantum computer
• Surface code architecture for donors and dots in silicon with imprecise and nonuniform qubit couplings
• Conditional control of donor nuclear spins in silicon using Stark shifts
• Efficient Dynamic Polarization of Phosphorus Nuclei in Silicon in Strong Magnetic Fields and Low Temperatures
• Valley-enhanced fast relaxation of gate-controlled donor qubits in silicon