EIGENFREQUENCIES REPULSION OF
MAGNETODYNAMIC MODES IN MAGNETIZED FERRITE RESONATORS FOR MILLIMETER
WAVEBAND
N. N. Movchan, M. A.
Popov
Taras Shevchenko National University of Kyiv
The paper is received
on December 26, 2013
Abstract. In the paper the repulsion of the magnetodynamic
modes resonant frequency in the ferrite disc-shaped and rectangular
parallelepiped-shaped millimeter band resonators have been investigated. In
particular, the initial repulsion of magnetodynamic modes eigenfrequencies at
low magnetic fields was studied both theoretically and experimentally. From numerical
calculations using the HFSS software package it was found that for the current
experimental conditions the predominant cause of the resonance frequencies initial
repulsion in the disk-shaped ferrite resonator is the distortion of the
cylindrical symmetry of the electromagnetic field around the resonator when it
is placed as inhomogeneity inside the waveguide. A method was proposed to
control the magnitude of the resonance frequencies initial repulsion of the
ferrite rectangular parallelepiped-shaped resonator by changing the shape of
the resonator. The possibility of reducing the resonance frequencies initial
repulsion from 1 GHz to 400 MHz and increasing the magnitude steepness
of the frequency vs. field dependence of the YIG resonators in low fields
(~ 100-200 Oe) from 0.5 MHz/Oe to 1 MHz/Oe was experimentally demonstrated.
Keywords:
ferrite resonator, magnetic tuning,
magnetodynamic modes, yttrium iron garnet.