Electromagnetic wave detector and image analyser using such a detector

Abstract

Abstract Electromagnetic wave detector with quantum wells. An illustrative embodiment of this detector makes it possible to detect a wave in the mid infrared range, by controlling the detector through optical pumping by means of a wave in the near infrared range. In this case it comprises a quantum well structure consisting of alternate first layers (2) and second layers (1, 3), these materials being such that there is a potential well in the conduction band and in the valence band of each first layer (1). The thickness of each first layer (1) is such that the electrons from the conduction band possess at least one discrete allowed energy level (e1), such that the energy difference (h.@1<0>) between this level (e1) and the bottom of the conduction band in the second layers (1, 3) is less than or equal to the energy corresponding to the frequency (@1) of the wave to be detected, and such that the energy difference between the ground level (h1) allowed for the holes in the valence band, and the ground level (e1) allowed for the electrons in the conduction band, corresponds to a frequency (@2<0>) near the frequency (@2) of the control wave. Application in particular to the measurement of optical power in a guide, the detector being practically transparent in the absence of the control wave; and application to image analysis by means of optical scanning. <IMAGE>

Inventors

• 👤 Dominique Delacourt
• 👤 Michel Papuchon
• 👤 Jean-Paul Pocholle

Bibliographic Details