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Ambipolar gate effect and low temperature magnetoresistance of ultrathin La0.8Ca0.2MnO3 Films

M. Eblen-Zayas·A. Bhattacharya·N. E. Staley·A. L. Kobrinskii·A. M. Goldman
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Abstract

Ultrathin La0.8Ca0.2MnO3 films have been measured in a field-effect geometry. The electric field due to the gate produces a large ambipolar decrease in resistance at low temperatures. This is attributed to the development of a pseudogap in the density of states and the couple of localized charge to strain. The gate effect and mangetoresistance are interpreted in a consistent framework. The implications for the low temperature behavior of a manganite film in the two dimensional limit are discussed.

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M. Eblen-Zayas, A. Bhattacharya, N. E. Staley, A. L. Kobrinskii, A. M. Goldman. 2004-07-23. Ambipolar gate effect and low temperature magnetoresistance of ultrathin La0.8Ca0.2MnO3 Films. https://doi.org/10.1103/physrevlett.94.037204

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