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Title: Optical Spin Polarization of a Narrow‐Linewidth Electron‐Spin Qubit in a Chromophore/Stable‐Radical System
Abstract

Photoexcited organic chromophores appended to stable radicals can serve as qubit and/or qudit candidates for quantum information applications. 1,6,7,12‐Tetra‐(4‐tert‐butylphenoxy)‐perylene‐3,4 : 9,10‐bis(dicarboximide) (tpPDI) linked to a partially deuterated α,γ‐bisdiphenylene‐β‐phenylallyl radical (BDPA‐d16) was synthesized and characterized by time‐resolved optical and electron paramagnetic resonance (EPR) spectroscopies. Photoexcitation of tpPDI‐BDPA‐d16results in ultrafast radical‐enhanced intersystem crossing to produce a quartet state (Q) followed by formation of a spin‐polarized doublet ground state (D0). Pulse‐EPR experiments confirmed the spin multiplicity ofQand yielded coherence times ofTm=2.1±0.1 μs and 2.8±0.2 μs forQandD0, respectively. BDPA‐d16eliminates the dominant1H hyperfine couplings, resulting in a single narrow line for both theQandD0states, which enhances the spectral resolution needed for good qubit addressability.

 
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NSF-PAR ID:
10393310
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Angewandte Chemie
Volume:
135
Issue:
6
ISSN:
0044-8249
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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