Abstract
The multiexciton quintet state, 5TT, generated as a singlet fission intermediate in pairs of molecular chromophores, is a promising candidate as a qubit or qudit in future quantum information science schemes. In this work, we synthesize a pyrene-bridged parallel tetracene dimer, TPT, with an optimized interchromophore coupling strength to prevent the dissociation of 5TT to two decorrelated triplet (T1) states, which would contaminate the spin-state mixture. Long-lived and strongly spin-polarized pure 5TT state population is observed via transient absorption spectroscopy and transient/pulsed electron paramagnetic resonance spectroscopy, and its lifetime is estimated to be >35 µs, with the dephasing time (T2) for the 5TT-based qubit measured to be 726 ns at 10 K. Direct relaxation from 1TT to the ground state does diminish the overall excited state population, but the exclusive 5TT population at large enough persistent density for pulsed echo determination of spin coherence time is consistent with recent theoretical models that predict such behavior for strict parallel chromophore alignment and large exchange coupling.
| Original language | English |
|---|---|
| Pages (from-to) | 11554-11565 |
| Number of pages | 12 |
| Journal | Chemical Science |
| Volume | 14 |
| Issue number | 41 |
| DOIs | |
| State | Published - Oct 2 2023 |
Bibliographical note
Publisher Copyright:© 2023 The Royal Society of Chemistry.
Funding
Work on transient absorption and time-resolved electron paramagnetic resonance spectroscopy was supported by the Solar Photochemistry Program of the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Chemical Sciences, Biosciences, and Geosciences. We acknowledge funding for steady-state spectroscopy and aggregation studies from the National Science Foundation (CHE-2102713). Q. A. and C. R. acknowledge funding from the National Science Foundation through the Designing Materials to Revolutionize and Engineer our Future (NSF DMREF) program under award number DMR 1627428, and thank the University of Kentucky Center for Computational Sciences and Information Technology Services Research Computing for their fantastic support and collaboration and use of the Lipscomb Compute Cluster and associated research computing resources. We thank Sean Parkin, University of Kentucky X-ray crystallography facility, for obtaining the TPT crystal structure. This work was authored by Alliance for Sustainable Energy, Limited Liability Company, the manager and operator of the National Renewable Energy Laboratory under Contract No. DE-AC36-08GO28308. The views expressed in the article do not necessarily represent the views of the Department of Energy or the U.S. Government. The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid‐up, irrevocable, worldwide license to publish or reproduce the published form of this work, or allow others to do so, for U.S. Government purposes.
| Funders | Funder number |
|---|---|
| Chemical Sciences, Geosciences, and Biosciences Division | |
| U.S. Government | |
| University of Kentucky Medical Center | |
| National Science Foundation (NSF) | DMR 1627428, CHE-2102713 |
| Michigan State University-U.S. Department of Energy (MSU-DOE) Plant Research Laboratory | |
| Office of Basic Energy Sciences | |
| National Renewable Energy Laboratory | DE-AC36-08GO28308 |
ASJC Scopus subject areas
- General Chemistry