Magnetic dipolar interaction between correlated triplets created by singlet fission in tetracene crystals

@article{Wang2015MagneticDI,
  title={Magnetic dipolar interaction between correlated triplets created by singlet fission in tetracene crystals},
  author={Rui Wang and Chunfeng Zhang and Bo Zhang and Yunlong Liu and Xiaoyong Wang and Min Xiao},
  journal={Nature Communications},
  year={2015},
  volume={6}
}
Singlet fission can potentially break the Shockley–Queisser efficiency limit in single-junction solar cells by splitting one photoexcited singlet exciton (S1) into two triplets (2T1) in organic semiconductors. A dark multiexciton state has been proposed as the intermediate connecting S1 to 2T1. However, the exact nature of this multiexciton state, especially how the doubly excited triplets interact, remains elusive. Here we report a quantitative study on the magnetic dipolar interaction between… 
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49 Citations

Anisotropic Geminate and Non-Geminate Recombination of Triplet Excitons in Singlet Fission of Single Crystalline Hexacene.

Singlet fission is known to improve solar energy utilization by circumventing the Shockley-Queisser thermodynamic limit. Understanding of triplet exciton generated by singlet fission is essential for…

Transport of Spin-Entangled Triplet Excitons Generated by Singlet Fission.

Temperature-dependent ultrafast transient absorption microscopy is employed to image the transport of singlet fission intermediates in single crystals of tetracene and indicates that 1[TT] could transport with a similar mechanism as the bright singlet excitons, which has important implications in designing materials for singlets fission and spintronic applications.

Vibronic exciton theory of singlet fission. I. Linear absorption and the anatomy of the correlated triplet pair state.

This work forms a model in which both electronic and vibrational degrees of freedom are treated microscopically and non-perturbatively, and uses pentacene as a prototypical material for singlet fission, and subjects the theory to comparison with measurements on polarization-resolved absorption of single crystals.

Weakly coupled triplet pair states probed by quantum beating in delayed fluorescence in tetracene crystals.

It is argued that the triplet pairs probed by the quantum beat spectrum are weakly coupled, i.e., the spatially separated 1(T⋯T) state which is valuable for elucidating the intrinsic mechanism of singlet fission.

Coupled double triplet state in singlet fission.

Starting from the early description of 1(TT) in polyenes, this perspective discusses formation mechanisms, spectroscopic signatures, and the scope of intertriplet interactions to enable efficient charge carrier extraction when employing singlet fission to generate charge carriers in a solar cell.

The entangled triplet pair state in acene and heteroacene materials

Entanglement of states is one of the most surprising and counter-intuitive consequences of quantum mechanics, with potent applications in cryptography and computing. In organic materials, one…

Magnetic Field Effects on Triplet Pair Generated by Singlet Fission in an Organic Crystal: Application of Radical Pair Model to Triplet Pair

Magnetic field effects (MFEs) on triplet pairs generated by singlet fission (SF) in an organic crystal, 1,6-diphenyl-1,3,5-hexatriene, were studied by steady-state fluorescence measurements under…

Efficient Singlet Fission and Triplet-Pair Emission in a Family of Zethrene Diradicaloids.

Singlet fission offers the potential to overcome thermodynamic limits in solar cells by converting the energy of a single absorbed photon into two distinct triplet excitons. However, progress is…

Spin Statistics for Triplet–Triplet Annihilation Upconversion: Exchange Coupling, Intermolecular Orientation, and Reverse Intersystem Crossing

Triplet–triplet annihilation upconversion (TTA-UC) has great potential to significantly improve the light harvesting capabilities of photovoltaic cells and is also sought after for biomedical…

Strongly exchange-coupled triplet pairs in an organic semiconductor

From biological complexes to devices based on organic semiconductors, spin interactions play a key role in the function of molecular systems. For instance, triplet-pair reactions impact operation of…

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