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arXiv · 1411.3733

Low-energy phonons and superconductivity in Sn$_{0.8}$In$_{0.2}$Te

Zhijun Xu·J. A. Schneeloch·Ruidan Zhong·J. A. Rodriguez-Rivera·L. Harriger·R. J. Birgeneau·Genda Gu·J. M. Tranquada·Guangyong Xu
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Abstract

We present neutron scattering measurements on low-energy phonons from a superconducting ($T_{c} = 2.7$~K) Sn$_{0.8}$In$_{0.2}$Te single crystal sample. The longitudinal acoustic phonon mode and one transverse acoustic branch have been mapped out around the (002) Bragg peak for temperatures of 1.7 K and 4.2 K. We observe a substantial energy width of the transverse phonons at energies comparable to twice the superconducting gap; however, there is no change in this width between the superconducting and normal states. We also confirm that the compound is well ordered, with no indications of structural instability.

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Zhijun Xu, J. A. Schneeloch, Ruidan Zhong, J. A. Rodriguez-Rivera, L. Harriger, R. J. Birgeneau, Genda Gu, J. M. Tranquada, Guangyong Xu. 2014-11-13. Low-energy phonons and superconductivity in Sn$_{0.8}$In$_{0.2}$Te. https://doi.org/10.1103/physrevb.91.054522

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