Role of photoinduced heating in transient photoconductivity in CMR materials

• Published in: Physica. B, Condensed matter Vol. 363; no. 1; pp. 76 - 81
• Main Authors: Noginova, N., Bonner, C.E.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15-06-2005; Elsevier
• Subjects: Colossal magnetoresistance; Colossal magnetoresistance materials; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Exact sciences and technology; Magnetic phase transitions; Magnetic properties and materials; Magnetotransport phenomena, materials for magnetotransport; Photoresponse; Physics; 72.40; 75.30V; Photoresponse; Magnetic phase transitions; 75.30K; 73.50P; Colossal magnetoresistance materials; Latent heat; Transient photoconductivity; 73.50P: 72.40 Colossal magnetoresistance materials: Photoresponse; Colossal magnetoresistance; Magnetic transitions; Heat treatments; Relaxation; Monocrystals; Thermodynamic model; Temperature effects; Visible radiation; Thermal conductivity
• ISSN: 0921-4526; 1873-2135
• DOI: 10.1016/j.physb.2005.02.034

The temperature dependence of the photoconductivity of La
1−
x
Sr
x
MnO
3 colossal magnetoresistance (CMR) films and single crystals has been studied using visible pulsed radiation. The responses in films and crystals have similar appearance but are in different time scales. Critical reduction of the relaxation rate was observed in vicinity of the transition temperature. The experimental results are explained with a simple thermodynamic model accounting for the latent heat of ferromagnetic transition as well as heat conduction and redistribution processes.