Electron spin relaxation of single phosphorus donors in metal-oxide-semiconductor nanoscale devices

Abstract

We analyze the electron spin relaxation rate $1/T_1$ of individual ion-implanted ${}^{31}$P donors, in a large set of metal-oxide-semiconductor (MOS) silicon nanoscale devices, with the aim of identifying spin relaxation mechanisms peculiar to the environment of the spins. The measurements are conducted at low temperatures ($T\approx 100$~mK), as a function of external magnetic field $B_0$ and donor electrochemical potential ${\mu }_{\mathrm{D}}$. We observe a magnetic field dependence of the form $1/T_1\propto B_0^5$ for $B_0\gtrsim 3$ T, corresponding to the phonon-induced relaxation typical of donors in the bulk. However, the relaxation rate varies by up to two orders of magnitude between different devices. We attribute these differences to variations in lattice strain at the location of the donor. For $B_0\lesssim 3$T, the relaxation rate changes to $1/T_1\propto B_0$ for two devices. This is consistent with relaxation induced by evanescent-wave Johnson noise created by the metal structures fabricated above the donors. At such low fields, where $T_1>1$s, we also observe and quantify the spurious increase of $1/T_1$ when the electrochemical potential of the spin excited state $|\uparrow ⟩$ comes in proximity to empty states in the charge reservoir, leading to spin-dependent tunneling that resets the spin to $|\downarrow ⟩$. These results give precious insights into the microscopic phenomena that affect spin relaxation in MOS nanoscale devices, and provide strategies for engineering spin qubits with improved spin lifetimes.

arXiv comment14 pages, 8 figures. Version 2 has extensive text revisions, typo corrections, and two extra authors

References in corpus (30)

• Single-shot read-out of an individual electron spin in a quantum dot
• Silicon Quantum Electronics
• A >99.9%-fidelity quantum-dot spin qubit with coherence limited by charge noise
• 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
• The Flux Qubit Revisited to Enhance Coherence and Reproducibility
• High-fidelity readout and control of a nuclear spin qubit in silicon
• Loss and heating of particles in small and noisy traps
• Silicon quantum processor with robust long-distance qubit couplings
• Electrically controlling single spin qubits in a continuous microwave field
• Cotunneling Spectroscopy in Few-Electron Quantum Dots
• Pauli Spin Blockade in a Highly Tunable Silicon Double Quantum Dot
• Transport through a double quantum dot in the sequential- and co- tunneling regimes
• Decoherence of electron spin qubits in Si-based quantum computers
• Architecture for high-sensitivity single-shot readout and control of the electron spin of individual donors in silicon
• Nanoscale broadband transmission lines for spin qubit control
• Energy Dependent Tunneling in a Quantum Dot
• Surface code architecture for donors and dots in silicon with imprecise and nonuniform qubit couplings
• Spin Relaxation due to Charge Noise
• Theory of one and two donors in Silicon
• Linear hyperfine tuning of donor spins in silicon using hydrostatic strain
• Strain-induced spin resonance shifts in silicon devices
• Stationary and transient leakage current in the Pauli spin blockade
• High-fidelity adiabatic inversion of a ${}^{31}\mathrm{P}$ electron spin qubit in natural silicon
• Relaxation in quantum dots due to evanescent-wave Johnson noise from a metallic backgate
• Indications of a soft cutoff frequency in the charge noise of a Si/SiGe quantum dot spin qubit
• Evanescent-wave Johnson Noise in small devices
• Tunneling induced spin dynamics in a quantum dot-lead hybrid system

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