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arXiv · 0711.0474

Electric field gradient induced effects in GaAs/AlGaAs modulation-doped structures and high frequency sensing

D. Seliuta·A. Juozapavicius·V. Gruzinskis·S. Balakauskas·S. Asmontas·G. Valusis·W. -H. Chow·P. Steenson·P. Harrison·A. Lisauskas·H. G. Roskos·K. Koehler
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Abstract

Electric field gradient effects induced by an asymmetrically in-plane shaped GaAs/AlGaAs modulation-doped structures of various design are investigated within 4-300 K temperature range. It is demonstrated that current-voltage characteristics of such structures at low, 4-80 K, temperatures exhibit well-pronounced asymmetry arising due to a presence of two different gradients of the electric field in a two dimensional electron gas. This phenomenon is caused by both, different accumulation of two-dimensional electrons due to asymmetrical shape of the structure and nonlocality in the electron drift velocity. Experiments are illustrated by a phenomenological model and Monte Carlo simulation. Possible applications of the effect to detect electromagnetic radiation of GHz and THz frequencies are discussed as well.

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D. Seliuta, A. Juozapavicius, V. Gruzinskis, S. Balakauskas, S. Asmontas, G. Valusis, W. -H. Chow, P. Steenson, P. Harrison, A. Lisauskas, H. G. Roskos, K. Koehler. 2008-04-21. Electric field gradient induced effects in GaAs/AlGaAs modulation-doped structures and high frequency sensing. https://arxiv.org/abs/0711.0474

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