The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 02, 1995
Filed:
Jan. 26, 1994
Sungho Jin, Millington, NJ (US);
Mark T McCormack, Summit, NJ (US);
Thomas H Tiefel, North Plainfield, NJ (US);
AT&T Corp., Murray Hill, NJ (US);
Abstract
We have discovered that the addition of a relatively small amount of Sr and/or Ba to La-Ca-Mn-O can yield material of improved magnetoresistive properties at room temperature and in a small applied field, as compared to the analogous Sr and/or Ba-free material. An exemplary composition is La.sub.0.55 Ca.sub.0.25 Sr.sub.0.08 MnO.sub.x. Material according to the invention has a substantially larger value of .vertline.d.rho./dH.vertline. than the analogous comparison material at 25.degree. C. and H.ltoreq.0.05 Tesla. Preferred compositions also can exhibit a substantially linear dependence of resistivity on applied magnetic field under these conditions, as well as have a relatively large value of zero field resistivity. The novel materials can advantageously be used in applications that involve sensing of a magnetic field, or of changes in such a field.