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Title: Switching circuit to improve the frequency modulation difference-intensity THz quantum cascade laser imaging

We demonstrate new switching circuit for difference-intensity THz quantum cascade laser (QCL) imaging by amplitude modulation and lock in detection. The switching circuit is designed to improve the frequency modulation so that it can stably lock the amplitude modulation of the QCL and the detector output. The combination of a voltage divider and a buffer in switching circuit to quickly switch the amplitude of the QCL biases of 15.8 V and 17.2 V is successfully to increase the frequency modulation up to ∼100 Hz.
Authors:
 [1] ; ; ; ; ;  [2]
  1. Department of Physics, Faculty of Science, University Putra Malaysia (Malaysia)
  2. School of Electronic and Electrical Engineering, University of Leeds, Woodhouse Lane, Leeds LS2 9JT (United Kingdom)
Publication Date:
OSTI Identifier:
22391517
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1657; Journal Issue: 1; Conference: PERFIK 2014: National Physics Conference 2014, Kuala Lumpur (Malaysia), 18-19 Nov 2014; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; AMPLITUDES; DESIGN; ELECTRIC POTENTIAL; FREQUENCY MODULATION; OPTICS; Q-SWITCHING; SOLID STATE LASERS; SWITCHING CIRCUITS