Hole Spin Relaxation in Ge/Si Core-Shell Nanowire Qubits

TY - JOUR

T1 - Hole Spin Relaxation in Ge/Si Core-Shell Nanowire Qubits

AU - Hu, Yongjie

AU - Kuemmeth, Ferdinand

AU - Lieber, Charles

AU - M. Marcus, Charles

PY - 2012/1

Y1 - 2012/1

N2 - Controlling decoherence is the biggest challenge in efforts to develop quantum information hardware1-3. Single electron spins in gallium arsenide are a leading candidate among implementations of solid-state quantum bits, but their strong coupling to nuclear spins produces high decoherence rates4-6. Group IV semiconductors, on the other hand, have relatively low nuclear spin densities, making them an attractive platform for spin quantum bits. However, device fabrication remains a challenge, particularly with respect to the control of materials and interfaces. Here, we demonstrate state preparation, pulsed gate control and charge-sensing spin readout of hole spins confined in a Ge-Si core-shell nanowire. With fast gating, we measure T 1 spin relaxation times of up to 0.6? ms in coupled quantum dots at zero magnetic field. Relaxation time increases as the magnetic field is reduced, which is consistent with a spin-orbit mechanism that is usually masked by hyperfine contributions.

AB - Controlling decoherence is the biggest challenge in efforts to develop quantum information hardware1-3. Single electron spins in gallium arsenide are a leading candidate among implementations of solid-state quantum bits, but their strong coupling to nuclear spins produces high decoherence rates4-6. Group IV semiconductors, on the other hand, have relatively low nuclear spin densities, making them an attractive platform for spin quantum bits. However, device fabrication remains a challenge, particularly with respect to the control of materials and interfaces. Here, we demonstrate state preparation, pulsed gate control and charge-sensing spin readout of hole spins confined in a Ge-Si core-shell nanowire. With fast gating, we measure T 1 spin relaxation times of up to 0.6? ms in coupled quantum dots at zero magnetic field. Relaxation time increases as the magnetic field is reduced, which is consistent with a spin-orbit mechanism that is usually masked by hyperfine contributions.

KW - cond-mat.mes-hall

KW - quant-ph

U2 - 10.1038/nnano.2011.234

DO - 10.1038/nnano.2011.234

M3 - Journal article

C2 - 22179569

SN - 1748-3387

VL - 7

SP - 47

EP - 50

JO - Nature Nanotechnology

JF - Nature Nanotechnology

ER -