Applied Superconductivity
I have been working on applications of high
temperature superconductors (HTS) for over a decade. The first "gadget" was a demonstration of magnetic shielding concieved
by David B. Opie (who got me into this business in the 1st place). What a beautiful experiment, unfortunately not available
for upload.
D.B. Opie, M.E. Read, S.K. Remillard,
M.J. Brown, W.J. Kossler, H.E. Schone, T.W. Button, and N. McAlford, Magnetic Shielding
by YBa2Cu3O7-δ Thick Films, IEEE Transactions on Applied Superconductivity, 3, 189 (1993).
After that I went to work on microwave filters fashioned out of these cold materials.
We made them out of thick film HTS:
S.K.
Remillard, A. Abdelmonem, D.S. Applegate, P.R. Radzikowski, and N.Lazzaro, Field
Deployable Microwave Filters Made from YBa2Cu3O7-δ Thick Films, Journal of
Superconductivity, 14, 47 (2001).
and out of thin film HTS:
H.R.
Yi, S.K. Remillard, and A. Abdelmonem, A Novel Ultra-Compact Resonator for Superconducting
Thin-Film Filters, IEEE Transactions on Microwave Theory and Techniques, 51,
no. 12, 2290-2296, (2003).
We
developed the entire system to support these filters including cryogenics, control electronics, low temperature low noise
amplifiers, and the ceramic material processes that make it all possible.
Basic
Superconductivity
This
actually follows the description of applied superconductivity because I used the superconducting devices to study
the superconductors. As a grad student I studied the contribution of granualrity to the microwave dissipation of HTS.
S.K. Remillard, M.E. Reeves, F.J. Rachford, and S.A. Wolf, The Surface Impedance of Granular High Temperature Superconductors in DC Magnetic Fields: Relationship to Frequency
Dependence, Journal of Applied Physics, 75,
4103 (1994).
It turns out this is quite important, and often significant. Did you know superconductors
have resistance? Well, at a high enough frequency you can even measure it.
In later years I turned to the question of the microwave nonlinear response of HTS.
This matters because nonlinear distortion is NOT something you want most devices to generate, yet superconductors seem
to kick out a bit of it.
S. K. Remillard, H.R. Yi and Amr Abdelmonem, Three-Tone
Intermodulation Distortion Generated by Superconducting Bandpass
Filters, IEEE Transactions on Applied Superconductivity, 13, 3797
(2003).
Download it
here:
Three-Tone Intermodulation Distortion (about 300 KB)
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