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arXiv · 0711.0460

Terahertz sensing by beryllium and silicon delta-doped GaAs/AlAs quantum wells

D. Seliuta·J. Kavaliauskas·B. Cechavicius·S. Balakauskas·G. Valusis·B. Sherliker·M. P. Halsall·P. Harrison·M. Lachab·S. P. Khanna·E. H. Linfield
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Abstract

Selective sensing of terahertz (THz) radiation by beryllium and silicon delta-doped GaAs/AlAs multiple quantum wells (MQWs) is demonstrated. A sensitivity up to 0.3 V/W within 0.5{4.2 THz in silicon- and up to 1 V/W within 4.2-7.3 THz range in beryllium-doped MQWs at liquid helium temperatures is shown. The built-in electric fields as estimated from the observed Franz-Keldysh oscillations in photoreflectance spectra were found to be located close to the cap and buffer layers of MQWs and vary from 18 kV/cm up to 49 kV/cm depending on the structure design.

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D. Seliuta, J. Kavaliauskas, B. Cechavicius, S. Balakauskas, G. Valusis, B. Sherliker, M. P. Halsall, P. Harrison, M. Lachab, S. P. Khanna, E. H. Linfield. 2007-11-03. Terahertz sensing by beryllium and silicon delta-doped GaAs/AlAs quantum wells. https://arxiv.org/abs/0711.0460

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