title: ZnGeSb2: a promising thermoelectric material with tunable ultra-high conductivity.
abstract: First principles calculations predict the promising thermoelectric material ZnGeSb2with a huge power factor (S2σ/τ) on the order of 3 × 1017W m-1K-2s-1, due to the ultra-high electrical conductivity scaled by a relaxation time of around 8.5 × 1025Ω-1m-1s-1, observed in its massive Dirac state. The observed electrical conductivity is higher than the well-established Dirac materials, and is almost carrier concentration independent with similar behaviour of both n and p type carriers, which may certainly attract device applications. The low range of thermal conductivity is also evident from the phonon dispersion. Our present study further reports the gradual phase change of ZnGeSb2from a normal semiconducting state, through massive Dirac states, to a topological semi-metal. The maximum power factor is observed in the massive Dirac states compared to the other two states.
authors.affiliation: Department of Physics, Indian Institute of Technology Hyderabad, Kandi, Sangareddy-502 285, Telangana, India. kanchana@iith.ac.in.
authors.forename: P C
authors.initials: PC
authors.lastname: Sreeparvathy
authors.affiliation: Department of Physics, Indian Institute of Technology Hyderabad, Kandi, Sangareddy-502 285, Telangana, India. kanchana@iith.ac.in.
authors.forename: V
authors.initials: V
authors.lastname: Kanchana
authors.affiliation: Advanced Centre of Research in High Energy Materials (ACRHEM), University of Hyderabad, Prof. C. R. Rao Road, Gachibowli, Hyderabad-500 046, Telangana, India.
authors.forename: G
authors.initials: G
authors.lastname: Vaitheeswaran
authors.affiliation: Department of Physics and Astronomy, Aarhus University, DK-8000 Aarhus C, Denmark.
authors.forename: N E
authors.initials: NE
authors.lastname: Christensen