High-Q open resonator structures with sparse spectrum
Abstract
The feasibility of producing coaxial open resonator structures with high Q-factor and sparse spectrum is considered, the gist being to use magnetic modes with higher-order radial index (H(MN), N not equal to 1). Such modes are neither exactly space modes nor exactly boundary modes but combine some characteristics of both. The principle of operation of such a resonator is cutting off a waveguide mode between two critical sections. The heat loss, characterized by the frequency-independent parameter delta = delta kQ (delta - field penetration depth in metal, k - wave number, Q - ohmic storage factor), is calculated approximately by using the Shukin-Leontovich impedance boundary conditions and applying the perturbation method to the surface impedance of the mirror material. For comparison, the heat loss in an open resonator structure operating with boundary modes is calculated analogously. Theoretical estimates agree fairly closely with experimental data. A frequency-tunable high-Q open resonator should be realizable by resorting to a biconic structure, with the outer conductor slightly tapering and the inner conductor movable.
- Publication:
-
USSR Rept Phys Math JPRS UPM
- Pub Date:
- April 1984
- Bibcode:
- 1984RpPhM.......13K
- Keywords:
-
- Cooling;
- Feasibility Analysis;
- Q Factors;
- Resonators;
- Impedance;
- Perturbation;
- Tuning;
- Waveguides;
- Electronics and Electrical Engineering