Because of the ultrafast and photon-driven nature of the transport in their active region, we demonstrate that quantum cascade lasers can be operated as resonantly amplified terahertz detectors with wide RF bandwidth. Tunable responsivities up to 50 V/W and noise equivalent powers down to 100 pW/Hz^1/2 are demonstrated at 4.7 THz. Constant peak responsivities with respect to the detector temperature are observed up to 80 K. Thanks to the ≈ps intersub-band lifetime, electrical bandwidths larger than 20 GHz can be obtained, allowing the detection of optical beatnotes from quantum cascade THz frequency combs.

中文翻译：

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再生太赫兹量子探测器

由于其有源区域中传输的超快和光子驱动特性，我们证明了量子级联激光器可以作为具有宽 RF 带宽的谐振放大太赫兹探测器运行。高达 50 V/W 的可调响应率和低至 100 pW/Hz ^{1/2 的}噪声等效功率在 4.7 THz 处得到证明。观察到相对于探测器温度的恒定峰值响应高达 80 K。由于 ≈ps 子带间寿命，可以获得大于 20 GHz 的电带宽，从而允许从量子级联太赫兹频率梳中检测光学拍音。