Imaging of a high-power millimeter-wave beam using a microwave gas breakdown initiated by a metal-dielectric screen

A technique for imaging of high-power millimeter-wave (MMW) beams using visible light emission from a surfaceinitiated microwave gas breakdown is discussed. A wave beam from pulsed 250 GHz gyrotron was imaged using a microwave gas breakdown initiated by a surface of a metal-dielectric screen. The screen was placed in a shallow metal chamber filled with helium with an admixture of argon. In the region, where MMW intensity was higher than the threshold intensity of the surface-initiated microwave gas breakdown, the intensity profile of a high-power MMW beam, which was obtained using this technique, was in good agreement with the data obtained using the thermographic technique.

[1]  G. Denisov,et al.  First experimental tests of powerful 250 GHz gyrotron for future fusion research and collective Thomson scattering diagnostics. , 2018, The Review of scientific instruments.

[2]  G. G. Denisov,et al.  Mode content analysis from intensity measurements in a few cross sections of oversized waveguides , 1997 .

[3]  Application of T-ray gyrotron developed for real-time non-destructive inspection to enhanced regeneration of cells , 2015, 2015 40th International Conference on Infrared, Millimeter, and Terahertz waves (IRMMW-THz).

[4]  S. Hay,et al.  A Millimeter-Wave Antenna Amplitude and Phase Measurement System , 2012, IEEE Transactions on Antennas and Propagation.

[5]  Won-Hui Lee,et al.  Food inspection system using terahertz imaging , 2014 .

[6]  W. M. Black,et al.  Breakdown of the atmosphere by emission from a millimeter‐wave free‐electron maser , 1983 .

[7]  A. Tsvetkov,et al.  Imaging of spatial distributions of the millimeter wave intensity by using the Visible Continuum Radiation from a discharge in a Cs–Xe mixture. Part II: Demonstration of application capabilities of the technique , 2017 .

[8]  T. Idehara,et al.  Development and Application of Gyrotrons at FIR UF , 2018, IEEE Transactions on Plasma Science.

[9]  D. K. Ul’yanov,et al.  Visualization of the microwave beam generated by a plasma relativistic microwave amplifier , 2017 .

[10]  R. B. McCowan,et al.  High-peak power K/sub a/-band gyrotron oscillator experiments with slotted and unslotted cavities , 1988 .

[11]  A. Vodopyanov,et al.  Breakdown of the heavy noble gases in a focused beam of powerful sub-THz gyrotron , 2019, Physics of Plasmas.

[12]  Li Jun-chang,et al.  An indirect algorithm of Fresnel diffraction , 2009 .

[13]  Yaroslav V. Getmanov,et al.  Novosibirsk Free Electron Laser—Facility Description and Recent Experiments , 2015, IEEE Transactions on Terahertz Science and Technology.

[14]  V. Malygin,et al.  Determination of the Mode Content in Spurious Microwave Radiation of the Gyrotron with a Straight Axisymmetric Output , 1999 .

[15]  S. D. Korovin,et al.  Millimeter-Wave HF Relativistic Electron Oscillators , 1987, IEEE Transactions on Plasma Science.

[16]  M. A. Shapiro,et al.  Plasma structures observed in gas breakdown using a 1.5 MW, 110 GHz pulsed gyrotron , 2009 .

[17]  Luchinin,et al.  Resonantly enhanced degenerate four-wave mixing of millimeter-wave radiation in gas. , 1992, Physical review letters.

[18]  Richard J. Temkin,et al.  Pressure Dependence of Plasma Structure in Microwave Gas Breakdown at 110 GHz , 2010 .

[19]  Manfred Thumm,et al.  Passive high-power microwave components , 2002 .

[20]  M. Pilossof,et al.  Note: A 95 GHz mid-power gyrotron for medical applications measurements. , 2015, The Review of scientific instruments.

[21]  S. I. Gritsinin,et al.  Non-self-sustained microwave discharge and the concept of a microwave air jet engine , 2002 .

[22]  Svilen Sabchevski,et al.  The Gyrotrons as Promising Radiation Sources for THz Sensing and Imaging , 2020, Applied Sciences.

[23]  S. Alberti,et al.  Infrared Measurements of the RF Output of 170-GHz/2-MW Coaxial Cavity Gyrotron and Its Phase Retrieval Analysis , 2009, IEEE Transactions on Plasma Science.