The spectra of mode loss in terahertz quantum cascade laser (THz QCL) with double metal waveguide (DMW) based on Au, Cu and Ag have been analysed. On the basis of measurements of the resistivity of DMW claddings for the temperature range from 4.2 to 300 K, the loss coefficients of THz radiation at Au-, Cu-, Ag-claddings are calculated. We show that the Ag-based DMW allows to reduce the losses by 1.3–7.0 cm-1 in comparison with Au-based DMW at room temperature. Our calculations show that the Ag-based DMW has slightly lower losses (~1 cm-1) than Cu-based DMW at cryogenic temperatures (below 100 K). The use of Cu-based DMW allows to reduce the loss coefficient in comparison with Ag-based DMW at higher temperatures (above 100 K). Temperature dependence of threshold gain for THz QCL with Au-, Cu-, Ag-based DMW are calculated. Taking into account the absorption of THz radiation by free carriers and optical phonons, the spectrum of total mode loss of THz QCL with different thickness of n+-GaAs top contact layer are analyses.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.