Abstract-Helicity sensitive terahertz radiation detection by dual-grating-gate high electron mobility transistors

P. Faltermeier¹, P. Olbrich¹, W. Probst¹, L. Schell¹, T. Watanabe², S. A. Boubanga-Tombet², T. Otsuji² and S. D. Ganichev¹
http://scitation.aip.org/content/aip/journal/jap/118/8/10.1063/1.4928969
1 Terahertz Center, University of Regensburg, 93040 Regensburg, Germany
2 Research Institute of Electrical Communication, Tohoku University, 980-8577 Sendai, Japan
J. Appl. Phys. 118, 084301 (2015); http://dx.doi.org/10.1063/1.4928969

We report on the observation of a radiation helicity sensitive photocurrent excited by terahertz (THz) radiation in dual-grating-gate (DGG) InAlAs/InGaAs/InAlAs/InP high electron mobility transistors (HEMT). For a circular polarization, the current measured between source and drain contacts changes its sign with the inversion of the radiation helicity. For elliptically polarizedradiation, the total current is described by superposition of the Stokes parameters with different weights. Moreover, by variation of gate voltages applied to individual gratings, the photocurrentcan be defined either by the Stokes parameter defining the radiation helicity or those for linearpolarization. We show that artificial non-centrosymmetric microperiodic structures with a two-dimensional electron system excited by THz radiation exhibit a dc photocurrent caused by the combined action of a spatially periodic in-plane potential and spatially modulated light. The results provide a proof of principle for the application of DGG HEMT for all-electric detection of the radiation's polarization state.