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Title: Precise high-fidelity electron–nuclear spin entangling gates in NV centers via hybrid dynamical decoupling sequences
Abstract

Color centers in solids, such as the nitrogen-vacancy center in diamond, offer well-protected and well-controlled localized electron spins that can be employed in various quantum technologies. Moreover, the long coherence time of the surrounding spinful nuclei can enable a robust quantum register controlled through the color center. We design pulse sequence protocols that drive the electron spin to generate robust entangling gates with these nuclear memory qubits. We find that compared to using Carr-Purcell-Meiboom-Gill (CPMG) alone, Uhrig decoupling sequence and hybrid protocols composed of CPMG and Uhrig sequences improve these entangling gates in terms of fidelity, spin control range, and spin selectivity. We provide analytical expressions for the sequence protocols and also show numerically the efficacy of our method on nitrogen-vacancy centers in diamond. Our results are broadly applicable to color centers weakly coupled to a small number of nuclear spin qubits.

 
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Award ID(s):
1741656
NSF-PAR ID:
10303667
Author(s) / Creator(s):
; ;
Publisher / Repository:
IOP Publishing
Date Published:
Journal Name:
New Journal of Physics
Volume:
22
Issue:
7
ISSN:
1367-2630
Page Range / eLocation ID:
Article No. 073059
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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