Regenerative Feedback Resonant Circuit to Detect Transient Changes in Electromagnetic Properties of Semi-Insulating Materials
A prototype regenerative feedback resonant circuit has been developed for measuring the transient spectral response due to perturbations in properties of various electromagnetic materials. The circuit can accommodate a variety of cavity resonators, shown here in the 8 GHz range, with passive quality factors (Qstat) as high as 7,000 depending upon material loading. The positive feedback enhanced dynamic quality factors (Qdyn) of resonator/material combinations in the regenerative circuit are on the order of 107 - 108. The theory, design, and implementation of the circuit is discussed along with real-time monitored example measurements of effects due to photon-induced charge carriers in high-resistivity silicon wafers and magnetic-field induced perturbations of yttrium-iron garnet.
- Research Organization:
- Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- AC05-76RL01830
- OSTI ID:
- 1091451
- Report Number(s):
- PNNL-SA-93493
- Journal Information:
- Review of Scientific Instruments, 84(8):Article No. 084703, Journal Name: Review of Scientific Instruments, 84(8):Article No. 084703
- Country of Publication:
- United States
- Language:
- English
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