Influence of Coupling Strength Between a Magnetic Quantum Dot and Quantum Hall Edge Channels on Valley-isospin-dependent Dirac Fermion Transport
| Autor: | Minsol Son, Nojoon Myoung, Jihyeon Jeon |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
010302 applied physics
Physics Condensed matter physics Unitarity Graphene Energy level splitting General Physics and Astronomy 02 engineering and technology Quantum Hall effect 021001 nanoscience & nanotechnology 01 natural sciences law.invention symbols.namesake Dirac fermion Quantum dot law Isospin 0103 physical sciences symbols 0210 nano-technology Graphene nanoribbons |
| Zdroj: | Journal of the Korean Physical Society. 76:318-322 |
| ISSN: | 1976-8524 0374-4884 |
| DOI: | 10.3938/jkps.76.318 |
| Popis: | We investigate Dirac fermion transport through opposite quantum Hall edge channels in armchair graphene nanoribbons where a magnetic quantum dot (MQD) is placed between the edges. The resulting conductance shows distinguished resonant features according to the angle Φ between the valley isospins at the opposite edges. Particularly, for Φ = 0, the conductance exhibits a behavior characteristic of dissipative resonances when the edge—dot distance is sufficiently small even though the unitarity of the whole system is conserved. As the edge—dot distance increases, a crossover behavior emerges between two distinct regimes: largely perturbed and unperturbed MQD. Resonant energy converges to a specific energy corresponding to the eigenenergy of the localized states in the unperturbed MQD. For sufficiently weak couplings, a fine splitting of the conductance resonances is observed, of which splitting energy is several μeV. The finding of these finely split localized states in the MQD allows us to better elucidate related electronic and transport properties in graphene. |
| Databáze: | OpenAIRE |
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