Strain-Induced InGaAs-Based Photoconductive Terahertz Antenna Detector
Strain-Induced InGaAs-Based Photoconductive Terahertz Antenna Detector
复制标题
应变感应 InGaAs 基光电导太赫兹天线探测器
DOI：
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发表时间：
2021
影响因子：
3.2
通讯作者：
D. Ponomarev
中科院分区：
文献类型：
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作者：
D. Lavrukhin;A. Yachmenev;Y. Goncharov;K. Zaytsev;R. Khabibullin;A. Buryakov;E. Mishina;D. Ponomarev
我们报道了一种基于光导天线（PCA）的太赫兹（THz）探测器，该探测器利用人工应变未掺杂InGaAs/InAlAs超晶格（SL）。利用我们的实验室脉冲太兹时域光谱仪，我们证明了应变诱导的基于SL的PCA探测器（SID）在光学探针功率<inline-formula>< text -math notation="LaTeX">$P_{ext{opt}}>$</ text -math></inline-formula> 6 mW时比基于晶格匹配InGaAs/InAlAs SL （LMD）的PCA探测器（SID）的优越性。两种探测器在780 nm激发波长处均具有3.5太赫兹的宽频宽，信噪比为<inline-formula>< text -math notation="LaTeX">$sim$</ text -math></inline-formula>70 dB。实验结果表明，两个检测器的行为发生了变化：当<inline-formula>< text -math符号="LaTeX">$P_{ext{opt}}$</ text -math></inline-formula> = 1 mW时，LMD的信噪比比SID的有所提高，而当<inline-formula>< text -math符号="LaTeX">$P_{ext{opt}}$</ text -math></inline-formula> = 10 mW时，LMD的信噪比比SID的有所提高。此外，SID的信噪比在<inline-formula>< text -math notation="LaTeX">$P_{ext{opt}}$</ text -math></inline-formula>时呈二次依赖关系，而LMD的信噪比在<inline-formula>< text -math notation="LaTeX">$P_{ext{opt}}}处开始趋于饱和；sim$</ text -math></inline-formula> 5 mW。此外，SID中的本底噪声几乎与探针功率无关，而LMD的本底噪声随着<inline-formula>< text -math notation="LaTeX">$P_{ext{opt}}$</ text -math></inline-formula>的增加而快速增长。我们相信，将SID耦合到光纤通信波长激光器可以为开发和制造便携且具有成本效益的太赫兹光导器件开辟一条道路。
We report on a terahertz (THz) detector based on a photoconductive antenna (PCA) utilizing an artificially strained undoped InGaAs/InAlAs superlattice (SL). Using our laboratory pulsed THz time-domain spectrometer, we demonstrate the advancement of the strain-induced SL-based PCA detector (SID) when operating with an optical probe power of <inline-formula><tex-math notation="LaTeX">$P_{ ext{opt}}>$</tex-math></inline-formula> 6 mW over the PCA detector based on a lattice-matched InGaAs/InAlAs SL (LMD). Both detectors demonstrate a broad frequency bandwidth of 3.5 THz at the excitation wavelength of 780 nm with a signal-to-noise ratio (SNR) of <inline-formula><tex-math notation="LaTeX">$sim$</tex-math></inline-formula>70 dB. The experimental results demonstrate a change in the behavior of two detectors: At <inline-formula><tex-math notation="LaTeX">$P_{ ext{opt}}$</tex-math></inline-formula> = 1 mW, the LMD shows a bit increased SNR compared to that for SID, while vice versa at <inline-formula><tex-math notation="LaTeX">$P_{ ext{opt}}$</tex-math></inline-formula> = 10 mW. Also, SID shows a quadratic dependence of its SNR on <inline-formula><tex-math notation="LaTeX">$P_{ ext{opt}}$</tex-math></inline-formula> while the SNR for LMD starts saturating at <inline-formula><tex-math notation="LaTeX">$P_{ ext{opt}};sim$</tex-math></inline-formula> 5 mW. Moreover, the noise floor in SID is almost independent on probe power, while the noise floor for LMD demonstrates a rapid growth with an increase of <inline-formula><tex-math notation="LaTeX">$P_{ ext{opt}}$</tex-math></inline-formula>. We believe that SID coupled to a fiber telecommunication wavelength laser could open a pathway toward the development and fabrication of portable and cost-effective THz photoconductive devices.