Giant spin-polarized current in a Dirac fermion system at cyclotron resonance
Abstract
We report on the observation of the giant spin-polarized photocurrent in HgTe/HgCdTe quantum well (QW) of critical thickness at which a Dirac spectrum emerges. Exciting QW of 6.6 nm width by terahertz (THz) radiation and sweeping magnetic field we detected a resonant photocurrent. Remarkably, the position of the resonance can be tuned from negative (-0.4 T) to positive (up to 1.2 T) magnetic fields by means of optical gating. The photocurent data, accompanied by measurements of radiation transmission as well as Shubnikov-de Haas and quantum Hall effects, give an evidence that the enhancement of the photocurrent is caused by cyclotron resonance in a Dirac fermion system. The developed theory shows that the current is spin polarized and originates from the spin dependent scattering of charge carriers heated by the radiation.
Keywords
Cite
@article{arxiv.1301.4572,
title = {Giant spin-polarized current in a Dirac fermion system at cyclotron resonance},
author = {P. Olbrich and C. Zoth and P. Vierling and K. -M. Dantscher and G. V. Budkin and S. A. Tarasenko and V. V. Bel'kov and D. A. Kozlov and Z. D. Kvon and N. N. Mikhailov and S. A. Dvoretsky and S. D. Ganichev},
journal= {arXiv preprint arXiv:1301.4572},
year = {2015}
}
Comments
5 pages with 5 figures + 3 pages of supplementary material with 1 figure