2014/06/30 by Sun-Yong Hwang, Rosa López, Rosa Lopez +3 · 3 citations
Chemistry · Materials Science · Physics and Astronomy · #Biasing #Chemistry #Condensed matter physics #Electron #Graphene research and applications #Physics #Polarization (electrochemistry) #Quantum and electron transport phenomena #Quantum mechanics #Spin (aerodynamics) #Spin Hall effect #Spin polarization #Temperature gradient #Thermoelectric effect #Topological Materials and Phenomena #Voltage #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.90.115301
published as Phys. Rev. B 90, 115301 (2014) · 10 pages, 7 figures
openalex publication_date 2014/09/02 · arxiv created 2014/09/03 · arxiv updated 2014/09/04 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We consider spin-polarized transport in a quantum spin Hall antidot system coupled to normal leads. Due to the helical nature of the conducting edge states, the screening potential at the dot region becomes spin dependent without external magnetic fields nor ferromagnetic contacts. Therefore, the electric current due to voltage or temperature differences becomes spin polarized, its degree of polarization being tuned with the dot level position or the base temperature. This spin-filter effect arises in the nonlinear transport regime only and has a purely interaction origin. Likewise, we find a spin polarization of the heat current, which is asymmetric with respect to the bias direction. Interestingly, our results show that a pure spin current can be generated by thermoelectric means: when a temperature gradient is applied, the created thermovoltage (Seebeck effect) induces a spin-polarized current for vanishingly small charge current. An analogous effect can be observed for the heat transport: a pure spin heat flows in response to a voltage shift even if the thermal current is zero.