2001/06/13 by A. F. Goncharov, V. V. Struzhkin, Goncharov, A. F. +15
Physics and Astronomy · #FOS: Physical sciences #Superconductivity (cond-mat.supr-con) #cond-mat.supr-con
paper · pdf · doi:10.48550/arxiv.cond-mat/0106258
12 pages, 8 fugures
arxiv created 2001/06/13 · arxiv updated 2009/11/30
We have observed a strongly broadened Raman band of MgB2 that shows anomalously large pressure dependence of its frequency. This band and its pressure dependence can be interpreted as the E2g zone center phonon, which is strongly anharmonic because of coupling to electronic excitations. The pressure dependence of Tc was measured to 14 GPa in hydrostatic conditions and can be explained only when a substantial pressure dependence of the Hopfield parameter h=N(0)<I2>~(V0/V)2.3(6)is taken into account.