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We demonstrate a high temperature performance quantum detector of Terahertz (THz) radiation based on three-dimensional metamaterial. The metamaterial unit cell consists of an inductor-capacitor (LC) resonator laterally coupled with antenna elements. The absorbing region, consisting of semiconductor quantum wells is contained in the strongly ultra-subwavelength capacitors of the LC structure. The high radiation loss of the antenna allows strongly increased collection efficiency for the incident THz radiation, while the small effective volume of the LC resonator allows intense light-matter coupling with reduced electrical area. As a result, our detectors operates at much higher temperatures than conventional quantum well detectors demonstrated so far.
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This commentary is written in response to arXiv:1907.13198. In this article, Zmuidzinas et al. raise questions about the results reported by our group in Nature Astronomy (DOI: 10.1038/s41550-019-0828-6) regarding our experimental methodology and our device performance metrics. As described in this Response, Zmuidzinas et al. have unfortunately missed some basic principles on impedance matching and the physics of photomixers and plasmonics that are at the heart of their categorical conclusions. Here, we correct these misunderstandings and discharge all of their flawed conclusions. Therefore, all of the results and conclusions reported in our Nature Astronomy manuscript remain correct, as before.
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