Paramagnetic garnet-type transparent ceramic, magneto-optical material and magneto-optical device

Patent metadata

Field	Value
Publication number	US-11535566-B2
Application number	US-201916413337-A
Country	US
Kind code	B2
Filing date	May 15, 2019
Priority date	May 18, 2018
Publication date	Dec 27, 2022
Grant date	Dec 27, 2022

Abstract

A paramagnetic garnet-type transparent ceramic is a sintered body of complex oxide represented by the following formula (1), comprising SiO2 as a sintering aid in an amount of more than 0% by weight to 0.1% by weight or less, and has a linear transmittance of 83.5% or more at the wavelength of 1,064 nm for an optical path length of 25 mm:(Tb1-x-yYxScy)3(Al1-zScz)5O12  (1)wherein 0.05≤x<0.45, 0<y<0.1, 0.5<1−x−y<0.95, and 0.004<z<0.2.

First claim

The invention claimed is:

1. A paramagnetic garnet-type transparent ceramic that is a sintered body of complex oxide represented by the following formula (1), comprising SiO 2 as a sintering aid in an amount of more than 0% by weight to 0.1% by weight or less, and has a linear transmittance of 83.5% or more at a wavelength of 1,064 nm for an optical path length of 25 mm:
(Tb 1-x-y Y x Sc y ) 3 (Al 1-z Sc z ) 5 O 12   (1)

wherein 0.05≤x<0.45, 0<y<0.1, 0.5<1−x−y<0.95, and 0.004<z<0.2.

2. The paramagnetic garnet-type transparent ceramic according to claim 1 , wherein a Verdet constant at the wavelength of 1,064 nm is 30 rad/(T·m) or more.

3. The paramagnetic garnet-type transparent ceramic according to claim 1 , wherein a maximum change amount of a focal position by a thermal lens is 0.25 m or less when laser light with the wavelength of 1,064 nm is input thereto with a beam diameter of 1.6 mm and input power of 100 W, for the optical path length of 25 mm.

4. The paramagnetic garnet-type transparent ceramic according to claim 1 , wherein an extinction ratio at the wavelength of 1,064 nm for the optical path length of 25 mm is 40 dB or more as a Faraday rotator.

5. The paramagnetic garnet-type transparent ceramic according to claim 1 , wherein a volume concentration of a scattering source is 3 ppm or less.

6. A magneto-optical material made of the paramagnetic garnet-type transparent ceramic according to claim 1 .

7. A magneto-optical device configured by using the magneto-optical material according to claim 6 .

8. The magneto-optical device according to claim 7 , comprising the paramagnetic garnet-type transparent ceramic as the Faraday rotator, wherein the magneto-optical device is an optical isolator which includes a polarization material in front of and behind the Faraday rotator on an optic axis and is usable at a wavelength band of 0.9 μm or more to 1.1 μm or less.

Assignees

• Shinetsu Chemical Co

Inventors

• Ikari Masanori

Classifications

• C04B2235/3224

  Rare earth oxide or oxide forming salts thereof, e.g. scandium oxide · CPC title

• C04B35/62625

  Wet mixtures · CPC title

• C01P2004/61

  Micrometer sized, i.e. from 1-100 micrometer · CPC title

• C04B2235/9646

  Optical properties · CPC title

• G02F1/093

  used as non-reciprocal devices, e.g. optical isolators, circulators (G02F1/0955 takes precedence) · CPC title