Localization of electronic states resulting from electronic topological transitions in the Mo$_{1-x}$Re$_x$ alloys: A photoemission study

L. S. Sharath Chandra; Shyam Sundar; Soma Banik; SK. Ramjan; M. K. Chattopadhyay; S. N. Jha; S. B. Roy

doi:10.1063/1.5143836

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arXiv · 2005.12835

Localization of electronic states resulting from electronic topological transitions in the Mo$_{1-x}$Re$_x$ alloys: A photoemission study

L. S. Sharath Chandra·Shyam Sundar·Soma Banik·SK. Ramjan·M. K. Chattopadhyay·S. N. Jha·S. B. Roy

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Abstract

We present the results of resonant photoemission spectroscopy experiments on the Mo$_{1-x}$Re$_{x}$ alloy compositions spanning over two electronic topological transitions (ETT) at the critical concentrations $x_{C1}$ = 0.05 and $x_{C2}$ = 0.11. The photoelectrons show an additional resonance ($R3$) in the constant initial state (CIS) spectra of the alloys along with two resonances ($R1$ and $R2$) which are similar to those observed in molybdenum. All the resonances show Fano-like line shapes. The asymmetry parameter $q$ of the resonances $R1$ and $R3$ of the alloys is observed to be large and negative. Our analysis suggests that the origin of large negative q is associated with phonon assisted inter band scattering between the Mo-like states and the narrow band that appeared due to the ETT.

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L. S. Sharath Chandra, Shyam Sundar, Soma Banik, SK. Ramjan, M. K. Chattopadhyay, S. N. Jha, S. B. Roy. 2020-05-26. Localization of electronic states resulting from electronic topological transitions in the Mo$_{1-x}$Re$_x$ alloys: A photoemission study. https://doi.org/10.1063/1.5143836

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