Browse Prior Art Database

Composite Film Curie Temperature Keeper

IP.com Disclosure Number: IPCOM000092268D
Original Publication Date: 1968-Nov-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 2 page(s) / 57K

Publishing Venue

IBM

Related People

Ahn, KY: AUTHOR

Abstract

An improvement is provided for a beam addressable memory which utilizes an electron beam or a light beam or both as a transducer with a memory medium of EuO. It can incorporate the technology described IBM Technical Disclosure Bulletin, Vol. 10, page 1471. The magneto-optic light switch and modulator described in the article utilizes a metallic mirror surface borne by on one side of a layer of EuO film or related compound having magneto-optical properties. The mirror surface reflection enhances the quantitative value of the intensity. This is modulated by the transverse Kerr effect in the EuO film. Such light switch and modulator utilizes reflected light from a magneto-optic film, especially the doped EuO and related compounds.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 53% of the total text.

Page 1 of 2

Composite Film Curie Temperature Keeper

An improvement is provided for a beam addressable memory which utilizes an electron beam or a light beam or both as a transducer with a memory medium of EuO. It can incorporate the technology described IBM Technical Disclosure Bulletin, Vol. 10, page 1471. The magneto-optic light switch and modulator described in the article utilizes a metallic mirror surface borne by on one side of a layer of EuO film or related compound having magneto-optical properties. The mirror surface reflection enhances the quantitative value of the intensity. This is modulated by the transverse Kerr effect in the EuO film. Such light switch and modulator utilizes reflected light from a magneto-optic film, especially the doped EuO and related compounds. When the usually linearly polarized light is reflected off a magneto-optic film, its intensity is modulated by the magnetization of the film. This effect has the relationship 2 delta = Delta I/I(o). Here Delta I is the change of reflected light intensity when the magnetization is switched from minus to plus saturation. I(o) is the reflected light intensity when the sample is demagnetized. When 2 delta becomes unity, this corresponds to an on-off switch.

For a typical memory to operate at 90 degrees K using doped EuO films having a Curie temperature of 140 degrees K, the remanent rotation is reduced by approximately 0.3 from the remanent value at 4.2 degrees K because of temperature dependence of magnetization. The remanent rotation at 4.2 degrees K is approximately 0.7 of saturation...