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An All-Cryogenic THz Transmission Spectrometer

P. J. Burke·J. P. Eisenstein·L. N. Pfeiffer·K. W. West
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Abstract

This paper describes a THz transmission spectrometer for the spectral range of 2-65 cm^-1 (100 GHz to 2 THz) with a spectral resolution of at least 1.8 cm^-1 (50 GHz) where the source, sample, and detector are all fully contained in a cryogenic environment. Cyclotron emission from a two-dimensional electron gas heated with an electrical current serves as a magnetic field tunable source. The spectrometer is demonstrated at 4.2 K by measuring the resonant cyclotron absorption of a second two dimensional electron gas. Unique aspects of the spectrometer are that 1) an ultra-broadband detector is used and 2) the emitter is run quasi-continuously with a chopping frequency of only 1 Hz. Since optical coupling to room temperature components is not necessary, this technique is compatible with ultra-low temperature (sub 100 mK) operation.

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P. J. Burke, J. P. Eisenstein, L. N. Pfeiffer, K. W. West. 2001-08-21. An All-Cryogenic THz Transmission Spectrometer. https://doi.org/10.1063/1.1426231

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