Ultra-fast carrier dynamics of La<sub>0.7</sub>Sr<sub>0.3</sub>MnO<sub>3</sub> thin films
ORAL
Abstract
Perovskite oxides (ABO3) are a promising class of transition metal oxides with a diverse range of properties such as multiferroicity and superconductivity. Many studies have been done on their structural and magnetic properties. Though, La0.7Sr0.3MnO3 (LSMO) is a semi-metal perovskite oxide, when grown with nanometer scale thicknesses, a band gap will form which can be close to the visible range. While this gap makes LSMO a potential choice for photovoltaic applications, there has been a limited understanding about the carrier dynamics of this oxide. LSMO thin films were fabricated by pulsed laser deposition on (100) SrTiO3 single crystal substrates. A degenerate pump probe setup with a femtosecond laser at 800nm was used to study the ultra-fast free carrier dynamics of LSMO thin films. Subpicosecond, subnanosecond and nanosecond dynamics are observed, which represent Auger, radiative and SRH recombination respectively. Moreover, in ultra-fast and fast regimes, oscillations were observed which can be due to phonons in the thin film or the substrate.
*We acknowledge funding support from ACS (PRF #56642-ND10) for students, NSF (DMR-1608656) for growth, and DOE (DE- SC0016176) for optics supplies.
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Presenters
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Saeed Yousefi Sarraf
- Physics and Astronomy department , West Virginia University
- Physics and astronomy, West Virginia Univ