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arXiv · 1208.5776

Hot electron bolometer heterodyne receiver with a 4.7-THz quantum cascade laser as a local oscillator

Jenna L. Kloosterman·Darren J. Hayton·Yuan Ren·Tsung-Yu Kao·Neils Hovenier·Jian-Rong Gao·Teun M. Klapwijk·Qing Hu·Christopher K. Walker·John L. Reno
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Abstract

We report on a heterodyne receiver designed to observe the astrophysically important neutral atomic oxygen [OI] line at 4.7448 THz. The local oscillator is a third-order distributed feedback Quantum Cascade Laser operating in continuous wave mode at 4.741 THz. A quasi-optical, superconducting NbN hot electron bolometer is used as the mixer. We recorded a double sideband receiver noise temperature (T^DSB_rec) of 815 K, which is ~7 times the quantum noise limit (h{\nu}/2k_B) and an Allan variance time of 15 s at an effective noise fluctuation bandwidth of 18 MHz. Heterodyne performance was confirmed by measuring a methanol line spectrum.

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Jenna L. Kloosterman, Darren J. Hayton, Yuan Ren, Tsung-Yu Kao, Neils Hovenier, Jian-Rong Gao, Teun M. Klapwijk, Qing Hu, Christopher K. Walker, John L. Reno. 2012-08-28. Hot electron bolometer heterodyne receiver with a 4.7-THz quantum cascade laser as a local oscillator. https://doi.org/10.1063/1.4774085

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