About cookies on this site Our websites require some cookies to function properly (required). In addition, other cookies may be used with your consent to analyze site usage, improve the user experience and for advertising. For more information, please review your options. By visiting our website, you agree to our processing of information as described in IBM’sprivacy statement. To provide a smooth navigation, your cookie preferences will be shared across the IBM web domains listed here.
Publication
CLEO 1991
Conference paper
Extremely High Electric Fields at Seml-Insulator/Metal Interfaces: Enhanced Generation of Ultrafast THz Radiation
Abstract
Previously, orders of magnitude enhancement of THz radiation has been observed when femtosecond optical pulses illuminate an electrically biased semiconductor-metal interface as compared with THz radiation emitted from free surfaces or photoconductive gaps. Indeed, the fastest THz emission was reported from a Metal-GaAs interfac.1 We have experimentally characterized this behavior in detail and have found that the results can be explained in terms of a previously unreported strong field enhancement near the anode. On an 80μm electrode separation, 90% of the applied potential exists within 5μm of the anode. This field enhancement results from two mechanisms; i) geometric effects, and ii) space charge formation near the anode. Numerical analysis of the current transport supports the interpretation of the experimental results and the existence of extremely large (105 V/cm) fields near the anode. © 1991 Optical Society of America