AI Article Synopsis
- The study demonstrates the detection of singlet fission in tetracene using a field-effect transistor (FET), highlighting its role in producing two triplet excitons from one photon.
- A single crystal FET was developed to provide a clearer understanding of spin-dependent processes under magnetic fields, as opposed to using less ordered materials.
- The researchers successfully manipulated spin-dependent processes to detect changes in magnetoconductance at room temperature by adjusting the voltage and illuminating the FET, linking the observed effects to the singlet fission phenomenon.
Article Abstract
We present the electrical detection of singlet fission in tetracene by using a field-effect transistor (FET). Singlet fission is a photoinduced spin-dependent process, yielding two triplet excitons from the absorption of a single photon. In this study, we engineered a more deterministic platform composed of an organic single crystal FET rather than amorphous or polycrystalline FETs to elucidate spin-dependent processes under magnetic fields. Despite the unipolar operation and relatively high mobility of single crystal tetracene FETs, we were able to manipulate spin dependent processes to detect magnetoconductance (MC) at room temperature by illuminating the FETs and tuning the bias voltage to adjust majority charge carrier density and trap occupancy. In considering the crystalline direction and magnetic field interactions in tetracene, we show the MC response observed in tetracene FETs to be the result of the singlet fission process.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6541755 | PMC |
| http://dx.doi.org/10.1021/acsnano.8b07625 | DOI Listing |
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