Title :
An optically-driven THz-modulator
Author :
Hecker, N.E. ; Libon, I.H. ; Hempel, M. ; Feldmann, J. ; Koch, M. ; Dawson, P.
Author_Institution :
Photonics & Optoelectron. Group, Ludwig-Maximilians-Univ., Munchen, Germany
Abstract :
Summary form only given. Mixed type-I/type-II GaAs-AlAs double quantum wells (QW) offer a means of generating electron-hole pairs with a lifetime which can exceed 400 /spl mu/s. For the sample chosen for the measurements discussed here, electrons excited in the /spl Gamma/-valley of the narrow well are transferred to the X-valley in the barrier material and subsequently to the /spl Gamma/-valley of the wider well. We have demonstrated that an optically-controlled carrier density excited by a low power cw-laser in a mixed type I/type II QW can be used as a variable THz modulator.
Keywords :
III-V semiconductors; aluminium compounds; electro-optical modulation; gallium arsenide; semiconductor quantum wells; submillimetre wave devices; /spl Gamma/-valley; 400 mus; GaAs-AlAs; X-valley; barrier material; electron-hole pair generation; lifetime; low power cw-laser; mixed type I/type II QW; mixed type-I/type-II GaAs-AlAs double quantum wells; narrow well; optically-controlled carrier density excitation; optically-driven THz-modulator; variable THz modulator; wider well; Choppers; Gallium arsenide; Laser excitation; Optical beams; Optical modulation; Optical polarization; Optical pumping; Optical receivers; Optical sensors; Ultrafast optics;
Conference_Titel :
Quantum Electronics and Laser Science Conference, 1999. QELS '99. Technical Digest. Summaries of Papers Presented at the
Conference_Location :
Baltimore, MD, USA
Print_ISBN :
1-55752-576-X
DOI :
10.1109/QELS.1999.807481
