TERMOACOUSTIC PROBE for the DETECTION OF microsecond TERAHERTZ PULSES
V. G. Andreev 1,
V. A. Vdovin 2
, Yu. K. Kalynov 3
1
Lomonosov Moscow State University, Faculty of Physics
2
Kotel'nikov Institute of Radio Engineering and Electronics of RAS
3 Applied Physics Institute of RAS
Received
December 11, 2012
Abstract. The design and general
concept of operation of a thermoacoustic detector for measurements of terahertz
microsecond pulses are discussed. Operation of the detector is based on effect
of acoustic signal generation when electromagnetic pulses are absorbed in the
layered structure: radiotransparent substrate – absorber – immersion liquid. Thin
metallic film of nanometer thickness sputtered onto the quartz substrate is
used as an absorber. The transformation of electromagnetic radiation into
acoustic pulse is performed in the film and in the liquid contacting with the
film. The acoustic pulse is detected by the broadband acoustic transducer and
registered with a digital oscilloscope. Application of the laboratory prototype of the thermoacoustic probe was for detection of
terahertz microsecond pulses generated by the large-orbit gyrotron is
discussed.
Keywords:
thermoacoustic detector, terahertz microsecond pulses, acoustic signal
generation, thin metallic film of nanometer thickness, gyrotron.