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Title: Skutterudites under pressure: An ab initio study

Abstract

Ab initio results on the band structure, density of states, and Fermi surface (FS) properties of LaRu{sub 4}X{sub 12} (X = P, As, Sb) are presented at ambient pressure as well as under compression. The analysis of density of states reveals the major contribution at the Fermi level to be mainly from the Ru-d and X-p states. We have a complicated Fermi surface with both electron and hole characters for all the three compounds which is derived mainly from the Ru-d and X-p states. There is also a simpler FS with hole character derived from the P-p{sub z} orbital for LaRu{sub 4}P{sub 12} and Ru-d{sub z{sup 2}} orbital in the case of As and Sb containing compounds. More interestingly, Fermi surface nesting feature is observed only in the case of the LaRu{sub 4}P{sub 12}. Under compression, we observe the topology of the complicated FS sheet of LaRu{sub 4}As{sub 12} to change around V/V{sub 0} = 0.85, leading to a behaviour similar to that of a multiband superconductor, and in addition, we have two more hole pockets centered around Γ at V/V{sub 0} = 0.8 for the same compound. Apart from this, we find the hole pocket to vanish at V/V{sub 0} = 0.8 in the case of LaRu{submore » 4}Sb{sub 12} and the opening of the complicated FS sheet gets reduced. The de Haas van Alphen calculation shows the number of extremal orbits in the complicated sheet to change in As and Sb containing compounds under compression, where we also observe the FS topology to change.« less

Authors:
;  [1];  [2]
  1. Department of Physics, Indian Institute of Technology Hyderabad, Ordnance Factory Estate, Yeddumailaram 502 205, Andhra Pradesh (India)
  2. School of Engineering Sciences and Technology (SEST), University of Hyderabad, Prof. C. R. Rao Road, Gachibowli, Hyderabad 500 046, Andhra Pradesh (India)
Publication Date:
OSTI Identifier:
22277949
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 115; Journal Issue: 9; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANTIMONIDES; COMPRESSION; ELECTRONS; FERMI LEVEL; HOLES; LANTHANUM COMPOUNDS; ORBITS; P STATES; RUTHENIUM ARSENIDES; RUTHENIUM PHOSPHIDES; SHEETS; SUPERCONDUCTORS

Citation Formats

Ram, Swetarekha, Kanchana, V., E-mail: kanchana@iith.ac.in, and Valsakumar, M. C. Skutterudites under pressure: An ab initio study. United States: N. p., 2014. Web. doi:10.1063/1.4867041.
Ram, Swetarekha, Kanchana, V., E-mail: kanchana@iith.ac.in, & Valsakumar, M. C. Skutterudites under pressure: An ab initio study. United States. doi:10.1063/1.4867041.
Ram, Swetarekha, Kanchana, V., E-mail: kanchana@iith.ac.in, and Valsakumar, M. C. 2014. "Skutterudites under pressure: An ab initio study". United States. doi:10.1063/1.4867041.
@article{osti_22277949,
title = {Skutterudites under pressure: An ab initio study},
author = {Ram, Swetarekha and Kanchana, V., E-mail: kanchana@iith.ac.in and Valsakumar, M. C.},
abstractNote = {Ab initio results on the band structure, density of states, and Fermi surface (FS) properties of LaRu{sub 4}X{sub 12} (X = P, As, Sb) are presented at ambient pressure as well as under compression. The analysis of density of states reveals the major contribution at the Fermi level to be mainly from the Ru-d and X-p states. We have a complicated Fermi surface with both electron and hole characters for all the three compounds which is derived mainly from the Ru-d and X-p states. There is also a simpler FS with hole character derived from the P-p{sub z} orbital for LaRu{sub 4}P{sub 12} and Ru-d{sub z{sup 2}} orbital in the case of As and Sb containing compounds. More interestingly, Fermi surface nesting feature is observed only in the case of the LaRu{sub 4}P{sub 12}. Under compression, we observe the topology of the complicated FS sheet of LaRu{sub 4}As{sub 12} to change around V/V{sub 0} = 0.85, leading to a behaviour similar to that of a multiband superconductor, and in addition, we have two more hole pockets centered around Γ at V/V{sub 0} = 0.8 for the same compound. Apart from this, we find the hole pocket to vanish at V/V{sub 0} = 0.8 in the case of LaRu{sub 4}Sb{sub 12} and the opening of the complicated FS sheet gets reduced. The de Haas van Alphen calculation shows the number of extremal orbits in the complicated sheet to change in As and Sb containing compounds under compression, where we also observe the FS topology to change.},
doi = {10.1063/1.4867041},
journal = {Journal of Applied Physics},
number = 9,
volume = 115,
place = {United States},
year = 2014,
month = 3
}
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