2020/08/14 by Alexandre Jaoui, Jaoui, Alexandre, G. Seyfarth +13 · 2 citations
Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Quantum and electron transport phenomena #Strongly Correlated Electrons (cond-mat.str-el) #Surface and Thin Film Phenomena
paper · pdf · doi:10.48550/arxiv.2008.06356
openalex publication_date 2020/08/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Lightly doped III-V semiconductor InAs is a dilute metal, which can be pushed\nbeyond its extreme quantum limit upon the application of a modest magnetic\nfield. In this regime, a Mott-Anderson metal-insulator transition, triggered by\nthe magnetic field, leads to a depletion of carrier concentration by more than\none order of magnitude. Here, we show that this transition is accompanied by a\ntwo-hundred-fold enhancement of the Seebeck coefficient which becomes as large\nas 11.3mV.K-1\≈ 130\(kB)/(e) at T=8K and B=29T. We find that the\nmagnitude of this signal depends on sample dimensions and conclude that it is\ncaused by phonon drag, resulting from a large difference between the scattering\ntime of phonons (which are almost ballistic) and electrons (which are almost\nlocalized in the insulating state). Our results reveal a path to distinguish\nbetween possible sources of large thermoelectric response in other low density\nsystems pushed beyond the quantum limit.\n