eprintid: 1474850
rev_number: 29
eprint_status: archive
userid: 608
dir: disk0/01/47/48/50
datestamp: 2016-03-23 16:27:11
lastmod: 2021-09-26 22:59:31
status_changed: 2016-03-23 16:27:11
type: article
metadata_visibility: show
creators_name: Ma, W-L
creators_name: Wolfowicz, G
creators_name: Li, S-S
creators_name: Morton, JJL
creators_name: Liu, R-B
title: Classical nature of nuclear spin noise near clock transitions of Bi donors in silicon
ispublished: pub
divisions: UCL
divisions: B04
divisions: C06
divisions: F64
note: ©2015 American Physical Society
abstract: Whether a quantum bath can be approximated as classical Gaussian noise is a fundamental issue in central spin decoherence and also of practical importance in designing noise-resilient quantum control. Spin qubits based on bismuth donors in silicon have tunable interactions with nuclear spin baths and are first-order insensitive to magnetic noise at so-called clock transitions (CTs). This system is therefore ideal for studying the quantum/classical Gaussian nature of nuclear spin baths since the qubit-bath interaction strength determines the back-action on the baths and hence the adequacy of a Gaussian noise model. We develop a Gaussian noise model with noise correlations determined by quantum calculations and compare the classical noise approximation to the full quantum bath theory. We experimentally test our model through a dynamical decoupling sequence of up to 128 pulses, finding good agreement with simulations and measuring electron spin coherence times approaching 1 s—notably using natural silicon. Our theoretical and experimental study demonstrates that the noise from a nuclear spin bath is analogous to classical Gaussian noise if the back-action of the qubit on the bath is small compared to the internal bath dynamics, as is the case close to CTs. However, far from the CTs, the back-action of the central spin on the bath is such that the quantum model is required to accurately model spin decoherence.
date: 2015-10-08
date_type: published
official_url: http://dx.doi.org/10.1103/PhysRevB.92.161403
oa_status: green
full_text_type: pub
language: eng
primo: open
primo_central: open_green
article_type_text: Journal Article
verified: verified_manual
elements_id: 1064469
doi: 10.1103/PhysRevB.92.161403
lyricists_name: Morton, John
lyricists_name: Wolfowicz, Gary
lyricists_id: JJLMO69
lyricists_id: GWOLF53
actors_name: Morton, John
actors_name: Smith, Robert
actors_id: JJLMO69
actors_id: RSSMI20
actors_role: owner
actors_role: impersonator
full_text_status: public
publication: PHYSICAL REVIEW B
volume: 92
article_number: 161403(R)
issn: 1098-0121
citation:        Ma, W-L;    Wolfowicz, G;    Li, S-S;    Morton, JJL;    Liu, R-B;      (2015)    Classical nature of nuclear spin noise near clock transitions of Bi donors in silicon.                   PHYSICAL REVIEW B , 92     , Article 161403(R).  10.1103/PhysRevB.92.161403 <https://doi.org/10.1103/PhysRevB.92.161403>.       Green open access   
 
document_url: https://discovery.ucl.ac.uk/id/eprint/1474850/7/Morton_1474850_paper83.pdf