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Updated: Jun 16, 2025
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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
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Persistence of Spin Coherence in a Crystalline Environment
Gerald Curran1, Zachary Rex1, Casper Xallan Wilson1
1Department of Physics, <a href="https://ror.org/012afjb06">Lehigh University</a>, Bethlehem, Pennsylvania 18018, USA.
Physical Review Letters
|August 19, 2024
Summary
Transport-induced dephasing (TID) suppresses quantum beats in entangled triplet pairs from singlet exciton fission. This effect, observed in rubrene crystals, depends on exciton hopping and energy shifts, revealing insights into molecular crystal dynamics.
Area of Science:
- Quantum mechanics
- Solid-state physics
- Materials science
Background:
- Singlet exciton fission generates entangled triplet pairs in molecular crystals.
- Quantum interference in these pairs can lead to observable fluorescence quantum beats.
- Understanding exciton dynamics is crucial for optoelectronic applications.
Purpose of the Study:
- To analyze quantum interference in triplet-exciton pairs.
- To introduce and investigate transport-induced dephasing (TID) as a mechanism suppressing quantum beats.
- To experimentally confirm the TID model in rubrene single crystals.
Main Methods:
- Theoretical modeling of quantum interference and TID.
- Experimental investigation using rubrene single crystals.
- Magnetic field manipulation to probe exciton dynamics.
Main Results:
- Identified TID as a key factor suppressing fluorescence quantum beats.
- Demonstrated that TID depends on exciton hopping rates and energy shifts.
- Observed sustained entanglement (>50 ns) but suppressed quantum beats (< few ns) in rubrene.
- Determined rubrene's zero-field parameters and exciton hopping rate (~150 ps).
Conclusions:
- TID significantly impacts quantum interference in molecular crystals.
- Exciton transport dynamics play a critical role in quantum phenomena.
- Rubrene crystals provide a platform for studying long-lived entangled states and dephasing mechanisms.
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