Anna De Vetter, James Normansell, José Palomo, Martin Mičica, Li Chen, Juliette Mangeney, Jerome Tignon, Lianhe H. Li, Alexander Giles Davies, Edmund H. Linfield, Joshua R. Freeman, Sukhdeep S. Dhillon
{"title":"腔基太赫兹光导天线的扩展光谱响应与量子级联激光器的相干探测","authors":"Anna De Vetter, James Normansell, José Palomo, Martin Mičica, Li Chen, Juliette Mangeney, Jerome Tignon, Lianhe H. Li, Alexander Giles Davies, Edmund H. Linfield, Joshua R. Freeman, Sukhdeep S. Dhillon","doi":"10.1515/nanoph-2025-0088","DOIUrl":null,"url":null,"abstract":"Coherent ultrafast detection has become an important method to study the temporal response of terahertz (THz) quantum cascade lasers (QCLs), bringing insights into the dynamics of modelocking and frequency comb operation in these complex structures. Coherent detection has been typically based on the use of nonlinear crystals and electro-optic sampling, which are less sensitive to QCLs operating at high THz frequencies. This is because their response drops rapidly with frequency owing to phase matching conditions. Here, we develop coherent detection based on THz photoconductive antennas in vertical quarter-wavelength cavities, where we can freely engineer the spectral response to enhance the THz detection at frequencies greater than 2 THz. We develop thick low temperature grown GaAs that is transferred onto polymer and metal coated substrates to create a cavity with an THz response that exceeds the response of non-cavity detectors. This vertical THz cavity also permits the planar electrode geometry to be designed independently. Indeed, we show that the THz cavity can be combined with large surface area single contact electrodes to further enhance the spectral response. Although this proof-of-principle coherent detection is not fully optimised, it is used to coherently resolve the temporal response of a double-metal THz QCL operating at 3 THz. This approach opens up perspectives to tune the response of THz photoconductive antennas and enhance their spectral response at a desired frequency.","PeriodicalId":19027,"journal":{"name":"Nanophotonics","volume":"46 1","pages":""},"PeriodicalIF":6.6000,"publicationDate":"2025-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Extended spectral response of cavity-based terahertz photoconductive antennas and coherent detection of quantum cascade lasers\",\"authors\":\"Anna De Vetter, James Normansell, José Palomo, Martin Mičica, Li Chen, Juliette Mangeney, Jerome Tignon, Lianhe H. Li, Alexander Giles Davies, Edmund H. Linfield, Joshua R. Freeman, Sukhdeep S. 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We develop thick low temperature grown GaAs that is transferred onto polymer and metal coated substrates to create a cavity with an THz response that exceeds the response of non-cavity detectors. This vertical THz cavity also permits the planar electrode geometry to be designed independently. Indeed, we show that the THz cavity can be combined with large surface area single contact electrodes to further enhance the spectral response. Although this proof-of-principle coherent detection is not fully optimised, it is used to coherently resolve the temporal response of a double-metal THz QCL operating at 3 THz. 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Extended spectral response of cavity-based terahertz photoconductive antennas and coherent detection of quantum cascade lasers
Coherent ultrafast detection has become an important method to study the temporal response of terahertz (THz) quantum cascade lasers (QCLs), bringing insights into the dynamics of modelocking and frequency comb operation in these complex structures. Coherent detection has been typically based on the use of nonlinear crystals and electro-optic sampling, which are less sensitive to QCLs operating at high THz frequencies. This is because their response drops rapidly with frequency owing to phase matching conditions. Here, we develop coherent detection based on THz photoconductive antennas in vertical quarter-wavelength cavities, where we can freely engineer the spectral response to enhance the THz detection at frequencies greater than 2 THz. We develop thick low temperature grown GaAs that is transferred onto polymer and metal coated substrates to create a cavity with an THz response that exceeds the response of non-cavity detectors. This vertical THz cavity also permits the planar electrode geometry to be designed independently. Indeed, we show that the THz cavity can be combined with large surface area single contact electrodes to further enhance the spectral response. Although this proof-of-principle coherent detection is not fully optimised, it is used to coherently resolve the temporal response of a double-metal THz QCL operating at 3 THz. This approach opens up perspectives to tune the response of THz photoconductive antennas and enhance their spectral response at a desired frequency.
期刊介绍:
Nanophotonics, published in collaboration with Sciencewise, is a prestigious journal that showcases recent international research results, notable advancements in the field, and innovative applications. It is regarded as one of the leading publications in the realm of nanophotonics and encompasses a range of article types including research articles, selectively invited reviews, letters, and perspectives.
The journal specifically delves into the study of photon interaction with nano-structures, such as carbon nano-tubes, nano metal particles, nano crystals, semiconductor nano dots, photonic crystals, tissue, and DNA. It offers comprehensive coverage of the most up-to-date discoveries, making it an essential resource for physicists, engineers, and material scientists.