Room-temperature quantum bit storage exceeding 39 minutes using ionized donors in silicon-28.
Quantum memories capable of storing and retrieving coherent information for extended times at room temperature would enable a host of new technologies. Electron and nuclear spin qubits using shallow neutral donors in semiconductors have been studied extensively but are limited to low temperatures (≲10 kelvin); however, the nuclear spins of ionized donors have the potential for high-temperature operation. We used optical methods and dynamical decoupling to realize this potential for an ensemble of phosphorous-31 donors in isotopically purified silicon-28 and observed a room-temperature coherence time of over 39 minutes. We further showed that a coherent spin superposition can be cycled from 4.2 kelvin to room temperature and back, and we report a cryogenic coherence time of 3 hours in the same system.
Department of Physics, Simon Fraser University, Burnaby, BC, V5A 1S6, Canada.
Kamyar
K
Saeedi
Stephanie
S
Simmons
Jeff Z
JZ
Salvail
Phillip
P
Dluhy
Helge
H
Riemann
Nikolai V
NV
Abrosimov
Peter
P
Becker
Hans-Joachim
HJ
Pohl
John J L
JJ
Morton
Mike L W
ML
Thewalt