SciTech Connect

Title: Giant magnetoresistance materials for magnetic recording technology

Giant magnetoresistance materials for magnetic recording technology This is the final report of a two-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). This work focused on a class of transition-metal-oxide (TMO) materials (LaMnO{sub 3} doped with Ca, Ba, or Sr) that exhibits an insulator-to-metal transition near a ferromagnetic phase transition temperature. This yields a very large magnetoresistance; thus these materials may have important uses as magnetic sensors in a variety of applications, ranging from automobiles to read heads for magnetic storage. In addition, the transport current in the ferromagnetic state is likely to be very highly polarized, which means that additional device applications using the phenomena of spin-polarized tunneling can be envisioned. Use of these materials as magnetic sensors depends upon learning to control the synthesis parameters (principally temperature, pressure and composition) to achieve a specific carrier concentration and/or mobility. A second challenge is the high magnetic fields ({ge}1 Tesla) currently required to achieve a large change in resistance. The authors began an investigation of two novel approaches to this field-sensitivity problem, involving the development of multilayer structures of the TMO materials. Finally, they began to explore the use of epitaxial strain as a means of changing the transport properties in more » thin-film multilayers. « less
Authors: ; ;
Publication Date:
OSTI Identifier:OSTI ID: 555556
Report Number(s):LA-UR--97-3377
ON: DE98001598; TRN: AHC29802%%135
DOE Contract Number:W-7405-ENG-36
Resource Type:Technical Report
Resource Relation:Other Information: PBD: [1997]
Research Org:Los Alamos National Lab., NM (United States)
Sponsoring Org:USDOE Assistant Secretary for Human Resources and Administration, Washington, DC (United States)
Country of Publication:United States
Language:English
Subject: 36 MATERIALS SCIENCE; 99 MATHEMATICS, COMPUTERS, INFORMATION SCIENCE, MANAGEMENT, LAW, MISCELLANEOUS; LANTHANUM OXIDES; MANGANESE OXIDES; MAGNETORESISTANCE; MAGNETIC STORAGE DEVICES; SYNTHESIS; RESEARCH PROGRAMS; DOPED MATERIALS; PHASE TRANSFORMATIONS; USES; RECORDING SYSTEMS; MEASURING INSTRUMENTS; CARRIER MOBILITY; COMPUTERS; SUPERLATTICES