Image of Dynamic Local Exchange Interactions in the dc Magnetoresistance of Spin-Polarized Current through a Dopant
| Autor: | Stephen R. McMillan, Nicholas J. Harmon, Michael E. Flatté |
|---|---|
| Přispěvatelé: | Fluids and Flows, Photonics and Semiconductor Nanophysics, Semiconductor Nanostructures and Impurities |
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
Physics
Quantum Physics Condensed Matter - Mesoscale and Nanoscale Physics Dopant Spins Condensed matter physics Magnetoresistance Exchange interaction FOS: Physical sciences General Physics and Astronomy 01 natural sciences Electrical contacts law.invention Magnetic field law Mesoscale and Nanoscale Physics (cond-mat.mes-hall) 0103 physical sciences Condensed Matter::Strongly Correlated Electrons Scanning tunneling microscope Quantum Physics (quant-ph) 010306 general physics Hyperfine structure |
| Zdroj: | Physical Review Letters, 125(25):257203. American Physical Society |
| ISSN: | 1079-7114 0031-9007 |
| Popis: | We predict strong, dynamical effects in the dc magnetoresistance of current flowing from a spin-polarized electrical contact through a magnetic dopant in a nonmagnetic host. Using the stochastic Liouville formalism we calculate clearly defined resonances in the dc magnetoresistance when the applied magnetic field matches the exchange interaction with a nearby spin. At these resonances spin precession in the applied magnetic field is canceled by spin evolution in the exchange field, preserving a dynamic bottleneck for spin transport through the dopant. Similar features emerge when the dopant spin is coupled to nearby nuclei through the hyperfine interaction. These features provide a precise means of measuring exchange or hyperfine couplings between localized spins near a surface using spin-polarized scanning tunneling microscopy, without any ac electric or magnetic fields, even when the exchange or hyperfine energy is orders of magnitude smaller than the thermal energy. |
| Databáze: | OpenAIRE |
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