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Effect of Al doping on the optical phonon spectrum in Mg(1-x)Al(x)B(2)

P. Postorino·A. Congeduti·P. Dore·A. Nucara·A. Bianconi·D. Di Castro·S. De Negri·A. Saccone
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Abstract

Raman and infrared absorption spectra of Mg(1-x)Al(x)B(2) have been collected for 0<x<0.5 in the spectral range of optical phonons. The x-dependence of the peak frequency, the width and the intensity of the observed Raman lines has been carefully analized. A peculiar x-dependence of the optical modes is pointed out for two different Al doping ranges. In particular the onset of the high-doping structural phase previously observed in diffraction measurements is marked by the appearence of new spectral components at high frequencies. A connection between the whole of our results and the observed suppression of superconductivity in the high doping region is established.

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P. Postorino, A. Congeduti, P. Dore, A. Nucara, A. Bianconi, D. Di Castro, S. De Negri, A. Saccone. 2001-06-19. Effect of Al doping on the optical phonon spectrum in Mg(1-x)Al(x)B(2). https://doi.org/10.1103/physrevb.65.020507

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