ePrints@IIScePrints@IISc Home | About | Browse | Latest Additions | Advanced Search | Contact | Help

Pressure-induced Lifshitz and structural transitions in NbAs and TaAs: experiments and theory

Gupta, Satyendra Nath and Singh, Anjali and Pal, Koushik and Muthu, D V S and Shekhar, C and Elghazali, Moaz A and Naumov, Pavel G and Medvedev, Sergey A and Felser, C and Waghmare, U V and Sood, A K (2018) Pressure-induced Lifshitz and structural transitions in NbAs and TaAs: experiments and theory. In: JOURNAL OF PHYSICS-CONDENSED MATTER, 30 (18).

[img] PDF
Jou_Phy_Con_Mat_30-18_2018.pdf - Published Version
Restricted to Registered users only

Download (3MB) | Request a copy
Official URL: http://dx.doi.org/10.1088/1361-648X/aab5e3

Abstract

High pressure Raman, resistivity and synchrotron x-ray diffraction studies on Weyl semimetals NbAs and TaAs have been carried out along with density functional theoretical (DFT) analysis to explain pressure induced structural and electronic topological phase transitions. The frequencies of first order Raman modes harden with increasing pressure, exhibiting a slope change at P-c(Nb) similar to 15 GPa for NbAs and P-c(Ta) similar to 16 GPa for TaAs. The resistivities of NbAs and TaAs exhibit a minimum at pressures close to these transition pressures and also a change in the bulk modulus is observed. Our first-principles calculations reveal that the transition is associated with an electronic Lifshitz transition at P-c(Nb) for NbAs while it is a structural phase transition from body centered tetragonal to hexagonal phase at P-c(Ta) for TaAs. Further, our DFT calculations show a structural phase transition at 24 GPa from body centered tetragonal phase to hexagonal phase.

Item Type: Journal Article
Additional Information: Copy right for this article belong to IOP PUBLISHING LTD, TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND
Department/Centre: Division of Physical & Mathematical Sciences > Physics
Depositing User: Id for Latest eprints
Date Deposited: 04 May 2018 18:50
Last Modified: 04 May 2018 18:50
URI: http://eprints.iisc.ac.in/id/eprint/59686

Actions (login required)

View Item View Item