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Thermal Control of a Dual Mode Parametric Sapphire Transducer

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 نشر من قبل Jacopo Belfi Dr.
 تاريخ النشر 2009
  مجال البحث فيزياء
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We propose a method to control the thermal stability of a sapphire dielectric transducer made with two dielectric disks separated by a thin gap and resonating in the whispering gallery (WG) modes of the electromagnetic field. The simultaneous measurement of the frequencies of both a WGH mode and a WGE mode allows one to discriminate the frequency shifts due to gap variations from those due to temperature instability. A simple model, valid in quasi equilibrium conditions, describes the frequency shift of the two modes in terms of four tuning parameters. A procedure for the direct measurement of them is presented.

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