Surface-modified GaAs terahertz plasmon emitter
نویسندگان
چکیده
We studied the THz emission from n-GaAs plasmon emitters modified by low-temperature-grown ~LT! GaAs surface layers. The THz emission is increased since the LT GaAs pins the Fermi level at a midgap position, increasing the surface depletion field. For a THz emitter with a 70-nm-thick LT GaAs layer we observe without external fields a THz emission intensity of 140 nW. In addition, the long-term performance of the modified emitters is improved by the LT GaAs surface layer. © 2002 American Institute of Physics. @DOI: 10.1063/1.1497192#
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