Miniature quantum-well microwave spectrometer operating at liquid-nitrogen temperatures

I. V. Kukushkin, S. A. Mikhailov, J. H. Smet, and K. von Klitzing. Appl. Phys. Lett. 86, 044101 (2005).

We demonstrate that a two-dimensional electron system fabricated from a GaAs∕AlGaAs quantum well in the presence of a magnetic field B possesses the ability to detectelectromagnetic radiation in a broad frequency range. Irradiation of the sample with microwaves produces a dc-photovoltage which oscillates as a function of B. The amplitude and the period of the oscillations are proportional to the radiation power and the wavelength, respectively. Successful operation of such a detector∕spectrometer is reported for microwave frequencies up to ∼150GHz and temperatures up to ∼80K. We do not anticipate any principal difficulties in extending the operation frequency further into the terahertz region.