Magnon-photon induced transparency in a cavity-quantum-electrodynamics system coupling yttrium-iron-garnet sphere

AbstractHybridizing collective spin excitations and a cavity with high cooperativity provides a new research subject in the field of cavity quantum electrodynamics and can also have potential applications to quantum information. Here we report an experimental study of cavity quantum electrodynamics with ferromagnetic magnons in a small yttrium-iron-garnet (YIG) sphere at both cryogenic and room temperatures. We observe for the first time a strong coupling of the same cavity mode to both a ferromagnetic-resonance (FMR) mode and a magnetostatic (MS) mode near FMR in the quantum limit. This is achieved at a temperature ~22 mK, where the average microwave photon number in the cavity is less than one. At room temperature, we also observe strong coupling of the cavity mode to the FMR mode in the same YIG sphere and find a slight increase of the damping rate of the FMR mode. These observations reveal the extraordinary robustness of the FMR mode against temperature. However, the MS mode becomes unobservable at room temperature in the measured transmission spectrum of the microwave cavity containing the YIG sphere. Our numerical simulations show that this is due to a drastic increase of the damping rate of the MS mode.

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Observation of electromagnetically induced transparency and absorption in Yttrium Iron Garnet loaded split ring resonator

Journal of Magnetism and Magnetic Materials ◽

10.1016/j.jmmm.2017.11.029 ◽

2018 ◽

Vol 451 ◽

pp. 235-242 ◽

Cited By ~ 10

Author(s):

Z.J. Tay ◽

W.T. Soh ◽

C.K. Ong

Keyword(s):

Yttrium Iron Garnet ◽

Ring Resonator ◽

Electromagnetically Induced Transparency ◽

Split Ring Resonator ◽

Yttrium Iron ◽

Split Ring ◽

Iron Garnet ◽

Induced Transparency

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Analysis and lattice imaging of a transitional event on garnets

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108490 ◽

1978 ◽

Vol 36 (1) ◽

pp. 270-271

Author(s):

J.Y. Laval

Keyword(s):

Yttrium Iron Garnet ◽

Reciprocal Lattice ◽

Transitional Zone ◽

Lattice Imaging ◽

Yttrium Iron ◽

X Ray ◽

Ionic Process ◽

The Matrix ◽

High Resolution Technique ◽

Iron Garnet

The exsolution of magnetite from a substituted Yttrium Iron Garnet, containing an iron excess may lead to a transitional event. This event is characterized hy the formation of a transitional zone at the center of which the magnetite nucleates (Fig.1). Since there is a contrast between the matrix and these zones and since selected area diffraction does not show any difference between those zones and the matrix in the reciprocal lattice, it is of interest to analyze the structure of the transitional zones.By using simultaneously different techniques in electron microscopy, (oscillating crystal method microdiffraction and X-ray microanalysis)one may resolve the ionic process corresponding to the transitional event and image this event subsequently by high resolution technique.

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