| Zugriffsnummer | 20500 |
| Dokumenttyp | Konferenzartikel |
| Sprache | Englisch |
| Titel | Room-temperature semiconductor modulators for free-space signal transmission with THz waves |
| Autor(in); Institution |
Kleine-Ostmann, Thomas; TU Braunschweig, Institut für Hochfrequenztechnik, Braunschweig, GERMANY
Pierz, Klaus; 2.5, Halbleiterphysik und Magnetismus, PTB-Braunschweig
Hein, Günter; 2.5, Halbleiterphysik und Magnetismus, PTB-Braunschweig
Dawson, Philip; UMIST, Physics Department, Manchester, UK
Koch, Martin; Institut für Hochfrequenztechnik, Technische Universität Braunschweig, GERMANY
|
| Quelle/Jahr | Nanosensing: materials and devices : 25 - 28 October 2004, Philadelphia, Pennsylvania, USA:(2004), 521 - 532 |
| Schriftenreihe | Proceedings of SPIE: 5593 |
| Herausgeber(in) |
Islam, M. Saif
|
| ISBN | 0-8194-5546-6 ; 978-0-8194-5546-8 |
| Verlag | Bellingham, Wash.: SPIE |
| Konferenzangaben | Optics East 2004, Philadelphia, Pa., October, 2004, USA |
| Freie Schlagworte | two-dimensional electron gas ; terahertz time-domain spectroscopy ; THz communications ; THz modulators |
| Zusammenfassung | We have used device structures based on the well-established technology for producing high electron mobility transistors to modulate the amplitude and the phase of broadband terahertz pulses. The application of an external gate voltage allowed us to deplete the two-dimensional electron gas, which in turn increased the transmission of the device to THz radiation. In differential transmission experiments at room-temperature we achieved a typical amplitude change of 2-3 % for THz pulses passing through the device. In this paper we present the results of a detailed investigation of the device behavior including I-V characteristics and capacitance measurements that reflect the depletion of the twodimensional electron gas. In a first demonstration experiment we were also able to use the modulator for audio signal transmission over a THz communication channel. To do this we modified a standard THz time-domain spectrometer to transmit signals up to 25 kHz imprinted onto a 75 MHz train of broadband THz pulses with frequencies between 100 GHz and 3 THz. |
