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Infrared absorption from Charge Density Waves in magnetic manganites

P. Calvani·G. De Marzi·P. Dore·S. Lupi·P. Maselli·F. D'Amore·S. Gagliardi·S-W. Cheong
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Abstract

The infrared absorption of charge density waves coupled to a magnetic background is first observed in two manganites La{1-x}Ca{x}MnO{3} with x = 0.5 and x = 0.67. In both cases a BCS-like gap 2 Delta (T), which for x=0.5 follows the hysteretic ferro-antiferromagnetic transition, fully opens at a finite T{0} < T{Neel}, with 2 Delta(T{0})/kT{c} close to 5. These results may also explain the unusual coexistence of charge ordering and ferromagnetism in La{0.5}Ca{0.5}MnO{3}.

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P. Calvani, G. De Marzi, P. Dore, S. Lupi, P. Maselli, F. D'Amore, S. Gagliardi, S-W. Cheong. 1998-10-09. Infrared absorption from Charge Density Waves in magnetic manganites. https://doi.org/10.1103/physrevlett.81.4504

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