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Infrared absorption in superconducting MgB2

C. S. Sundar·A. Bharathi·M. Premila·T. N. sairam·S. Kalavathi·G. L. N. Reddy·V. S. Sastry·Y. Hariharan·T. S. Radhakrishnan
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Abstract

Infrared absorption measurements in the range of 125 to 700 cm^(-1) have been carried out as a function of temperature upto 5 K in MgB2. The absorption spectrum is characterised by a broad band centred at 485 cm^{-1}, with shoulders at 333 and 387 cm^{-1}. Studies on the temperature dependence of absorption, indicate that these modes initially harden with the lowering of temperature, and this trend is arrested at ~ 100 K, below which they soften. Further, in the case of the mode at 333 cm^{-1}, there is a distinct softening associated with the superconducting transition at 39 K. The implications of these experimental results in the context of superconductivity in MgB2 are discussed.

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C. S. Sundar, A. Bharathi, M. Premila, T. N. sairam, S. Kalavathi, G. L. N. Reddy, V. S. Sastry, Y. Hariharan, T. S. Radhakrishnan. 2001-04-19. Infrared absorption in superconducting MgB2. https://arxiv.org/abs/cond-mat/0104354

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