Investigation of sapphire-based whispering-gallery mode resonators as transfer standard thermometers

An investigation on the metrological performance of thermometers based on spherical-sapphire whispering-gallery mode (WGM) resonators was carried out and reported in this work. In view of its use in industrial applications as a transfer standard with full sensor interchangeability, several thermometers were built with different sapphires having the same, nominal, specifications and a series of tests were performed in the temperature range from −40 to 85 °C in order to explore the repeatability and reproducibility of the resulting temperature measurement systems. The repeatability, stability and measurement accuracy of each thermometer were assessed and compared. A single calibrated WGM thermometer affords a measurement uncertainty of few millikelvins. An overall temperature accuracy of 20 mK can be routinely achieved.

[1]  M de Podesta,et al.  Acoustic gas thermometry , 2014 .

[2]  V. Fernicola,et al.  A temperature sensor based on a whispering gallery mode resonator , 2013 .

[3]  J. Krupka,et al.  The dependence of the permittivity of sapphire on thermal deformation at cryogenic temperatures , 2003 .

[4]  Jerzy Krupka,et al.  A dielectric resonator for measurements of complex permittivity of low loss dielectric materials as a function of temperature , 1998 .

[5]  Michael E. Tobar,et al.  Use of whispering-gallery modes for complex permittivity determinations of ultra-low-loss dielectric materials , 1999 .

[6]  J. Krupka,et al.  Room temperature measurement of the anisotropic loss tangent of sapphire using the whispering gallery mode technique , 2006, IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control.

[7]  Safieddin Safavi-Naeini,et al.  Whispering-gallery-mode resonance sensor for dielectric sensing of drug tablets , 2009 .

[8]  Gregory F. Strouse,et al.  Sapphire Whispering Gallery Thermometer , 2007 .

[9]  Michael E. Tobar,et al.  Complex permittivity of some ultralow loss dielectric crystals at cryogenic temperatures , 1999 .

[10]  H. Yoshikawa,et al.  Permittivity measurements at millimeter wave frequencies using dielectric rod resonator excited by NRD-guide , 2006 .

[11]  A low-cost instrument for the measurement of microwave resonances in quasi-spherical cavities , 2012, 2012 IEEE International Instrumentation and Measurement Technology Conference Proceedings.

[12]  J. Krupka,et al.  Dependence of the dielectric permittivity of single-crystal quartz on thermal deformation at cryogenic temperatures , 2007 .

[13]  Jerzy Krupka,et al.  Frequency domain complex permittivity measurements at microwave frequencies , 2006 .

[14]  Michael E. Tobar,et al.  Dielectric frequency - temperature- compensated microwave whispering-gallery-mode resonators , 1997 .

[15]  Jerzy Krupka,et al.  Precise measurements of the complex permittivity of dielectric materials at microwave frequencies , 2003 .

[16]  V. Fernicola,et al.  Spherical-sapphire-based whispering gallery mode resonator thermometer. , 2012, The Review of scientific instruments.