The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
We have combined few-cycle THz spectroscopy with quantum cascade technology. This combination allows to perform unique THz time-domain measurements of THz-QCLs. By coupling the few-cycle THz pulse into the waveguide of the QCL, the processes within the active zone can be probed. This gives direct information regarding the energy, dynamics and coherence of transitions in the QCL structure. In addition,...
Terahertz (THz) time-domain spectroscopy is used to investigate the gain and losses of a THz quantum cascade laser (QCL) operating at 2.86 THz. This measurement technique allows access to the amplitude and phase spectra, allowing the direct determination of the gain. At the emission frequency of the QCL, a value of 6.5 cm-1 is found. The gain can also be studied as a function of different operating...
Terahertz time-domain spectroscopy is used to determine the gain of terahertz quantum-cascade lasers. Gain clamping and spectral gain narrowing are observed above threshold, giving insight into subband alignment as a function of the applied voltage.
In this paper we present a very compact THz cyclotron resonance spectrometer that operates in the range 3 to 30 THz. This range is covered by choosing, respectively, several GaAs/AlGaAs quantum cascade lasers (QCL) for excitation, and either by Boron doped Silicon or Gallium doped Germanium photoconductors for detection. The system is made portable by aligning the quantum cascade laser, the sample,...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.