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arXiv · 2202.09678

Entangled, Spin-polarized Excitons from Singlet Fission in a Rigid Dimer

Ryan D. Dill·Kori E. Smyser·Niels H. Damrauer·Joel D. Eaves
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Abstract

Singlet fission, a process that splits a singlet exciton into a biexciton, has promise in quantum information. We report time-resolved electron paramagnetic resonance measurements on a molecule, TIPS-BP1$'$, designed to exhibit strongly state-selective relaxation to specific magnetic spin sublevels. The resulting optically pumped "spin polarization" is a nearly pure initial state from the ensemble. The long-lived spin coherences modulate the signal intrinsically, allowing a new measurement scheme that substantially removes noise and uncertainty in the magnetic resonance spectra. A nonadiabatic transition theory with a minimal number of spectroscopic parameters allows the quantitative assignment and interpretation of the spectra. The rigid, covalently bound dimer, TIPS-BP1$'$, supports persistent spin coherences at temperatures far higher than those used in conventional quantum hardware.

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Ryan D. Dill, Kori E. Smyser, Niels H. Damrauer, Joel D. Eaves. 2022-02-19. Entangled, Spin-polarized Excitons from Singlet Fission in a Rigid Dimer. https://arxiv.org/abs/2202.09678

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