scholarly journals Breakdown of the nuclear-spin-temperature approach in quantum-dot demagnetization experiments

2009 ◽  
Vol 5 (6) ◽  
pp. 407-411 ◽  
Author(s):  
P. Maletinsky ◽  
M. Kroner ◽  
A. Imamoglu
Keyword(s):  
Quantum Dot ◽  
Nuclear Spin ◽  
Spin Temperature

scholarly journals Fundamental limits of electron and nuclear spin qubit lifetimes in an isolated self-assembled quantum dot

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
George Gillard ◽  
Ian M. Griffiths ◽  
Gautham Ragunathan ◽  
Ata Ulhaq ◽  
Callum McEwan ◽  
...  
Keyword(s):  
Quantum Dot ◽  
Spin Relaxation ◽  
Nuclear Spin ◽  
Operating Conditions ◽  
External Control ◽  
Spin Qubits ◽  
Fundamental Limits ◽  
Trade Offs ◽  
Wide Range ◽  
Spin Qubit

AbstractCombining external control with long spin lifetime and coherence is a key challenge for solid state spin qubits. Tunnel coupling with electron Fermi reservoir provides robust charge state control in semiconductor quantum dots, but results in undesired relaxation of electron and nuclear spins through mechanisms that lack complete understanding. Here, we unravel the contributions of tunnelling-assisted and phonon-assisted spin relaxation mechanisms by systematically adjusting the tunnelling coupling in a wide range, including the limit of an isolated quantum dot. These experiments reveal fundamental limits and trade-offs of quantum dot spin dynamics: while reduced tunnelling can be used to achieve electron spin qubit lifetimes exceeding 1 s, the optical spin initialisation fidelity is reduced below 80%, limited by Auger recombination. Comprehensive understanding of electron-nuclear spin relaxation attained here provides a roadmap for design of the optimal operating conditions in quantum dot spin qubits.

scholarly journals Exchange Control of Nuclear Spin Diffusion in a Double Quantum Dot

2010 ◽  
Vol 104 (23) ◽  
Author(s):  
D. J. Reilly ◽  
J. M. Taylor ◽  
J. R. Petta ◽  
C. M. Marcus ◽  
M. P. Hanson ◽  
...  
Keyword(s):  
Quantum Dot ◽  
Nuclear Spin ◽  
Spin Diffusion ◽  
Double Quantum ◽  
Double Quantum Dot ◽  
Exchange Control

scholarly journals Quantum interface of an electron and a nuclear ensemble

Science ◽  
2019 ◽  
Vol 364 (6435) ◽  
pp. 62-66 ◽  
Author(s):  
D. A. Gangloff ◽  
G. Éthier-Majcher ◽  
C. Lang ◽  
E. V. Denning ◽  
J. H. Bodey ◽  
...  
Keyword(s):  
Quantum Dot ◽  
Nuclear Spin ◽  
Building Blocks ◽  
Spin Excitation ◽  
Many Body ◽  
Quantum Objects ◽  
All Optical ◽  
Spin Qubit ◽  
Many Body Systems ◽  
Optical Rotations

Coherent excitation of an ensemble of quantum objects underpins quantum many-body phenomena and offers the opportunity to realize a memory that stores quantum information. Thus far, a deterministic and coherent interface between a spin qubit and such an ensemble has remained elusive. In this study, we first used an electron to cool the mesoscopic nuclear spin ensemble of a semiconductor quantum dot to the nuclear sideband–resolved regime. We then implemented an all-optical approach to access individual quantized electronic-nuclear spin transitions. Lastly, we performed coherent optical rotations of a single collective nuclear spin excitation—a spin wave. These results constitute the building blocks of a dedicated local memory per quantum-dot spin qubit and promise a solid-state platform for quantum-state engineering of isolated many-body systems.

scholarly journals Qubit Protection in Nuclear-Spin Quantum Dot Memories

2009 ◽  
Vol 103 (1) ◽  
Author(s):  
Z. Kurucz ◽  
M. W. Sørensen ◽  
J. M. Taylor ◽  
M. D. Lukin ◽  
M. Fleischhauer
Keyword(s):  
Quantum Dot ◽  
Nuclear Spin ◽  
Spin Quantum
Sign in / Sign up

Export Citation Format

Share Document