Ultrafast mid-infrared dynamics in the colossal magnetoresistance pyrochlore Tl[sub 2]Mn[sub 2]O[sub 7]
- Rohib P.
- Richard D.
An optical pump, mid-infrared (IR) probe system is used to investigate ultrafast temperature-dependent dynamics of the colossal magnetoresistance pyrochlore Tl{sub 2}Mn{sub 2}O{sub 7}. The dynamics change appreciably near the Curie temperature (T{sub c}), indicating a dependence on ferromagnetic ordering. Colossal magnetoresistance (CMR) materials, in which the electrical resistance changes drastically with application of a magnetic field, have received a great deal of attention in recent years, both due to fundamental interest in this phenomenon as well as potential applications in areas such as magnetic sensing and recording. The best known example of these materials are the ferromagnetic perovskite manganites such as La{sub 1-x}Sr{sub x}MnO{sub 3}, in which the CMR mechanism originates from the combined effects of double exchange and Jahn-Teller distortions. Ultrafast optical spectroscopy has contributed to an understanding of the manganites by differentiating between the relative contributions of the lattice and spin degrees of freedom.
- Research Organization:
- Los Alamos National Laboratory
- Sponsoring Organization:
- DOE
- OSTI ID:
- 977549
- Report Number(s):
- LA-UR-04-2554
- Country of Publication:
- United States
- Language:
- English
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