Electron Spin Relaxation of Hole and Electron Polarons in π-Conjugated Porphyrin Arrays: Spintronic Implications
| Autor: | Paul R. Frail, Jeff Rawson, Paul J. Angiolillo, Michael J. Therien, Isabella Goodenough |
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| Rok vydání: | 2015 |
| Předmět: |
Spintronics
Condensed matter physics Magnetoresistance Electron Conjugated system Polaron Porphyrin Surfaces Coatings and Films law.invention chemistry.chemical_compound chemistry law Materials Chemistry Condensed Matter::Strongly Correlated Electrons Physical and Theoretical Chemistry Electron paramagnetic resonance Saturation (magnetic) |
| Zdroj: | The journal of physical chemistry. B. 119(24) |
| ISSN: | 1520-5207 |
| Popis: | Electron spin resonance (ESR) spectroscopic line shape analysis and continuous-wave (CW) progressive microwave power saturation experiments are used to probe the relaxation behavior and the relaxation times of charged excitations (hole and electron polarons) in meso-to-meso ethyne-bridged (porphinato)zinc(II) oligomers (PZnn com- pounds), which can serve as models for the relevant states generated upon spin injection. The observed ESR line shapes for the PZnn hole polaron ((PZnn) + ) and electron polaron ((PZnn) − ) states evolve from Gaussian to more Lorentzian as the oligomer length increases from 1.9 to 7.5 nm, with solution-phase (PZnn) + and (PZnn) − spin−spin (T2) and spin−lattice (T1) relaxation times at 298 K ranging, respectively, from 40 to 230 ns and 0.2 to 2.3 μs. Notably, these very long relaxation times are preserved in thick films of these species. Because the magnitudes of spin−spin and spin−lattice relaxation times are vital metrics for spin dephasing in quantum computing or for spin-polarized transport in magnetoresistive structures, these results, coupled with the established wire-like transport behavior across metal−dithiol-PZnn−metal junctions, present meso-to-meso ethyne-bridged multiporphyrin systems as leading candidates for ambient-temperature organic spintronic applications. |
| Databáze: | OpenAIRE |
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