title: Thermal transport and strong mass renormalization in NiCl2-4SC(NH2)2.
abstract: Several quantum paramagnets exhibit magnetic-field-induced quantum phase transitions to an antiferromagnetic state that exists for H c1 ≤ H ≤ H c2. For some of these compounds, there is a significant asymmetry between the low- and high-field transitions. We present specific heat and thermal conductivity measurements in NiCl2-4SC(NH2)2, together with calculations which show that the asymmetry is caused by a strong mass renormalization due to quantum fluctuations for H ≤ H c1 that are absent for H ≥ H c2. We argue that the enigmatic lack of asymmetry in thermal conductivity is due to a concomitant renormalization of the impurity scattering.
authors.affiliation: MPA-CMMS, LANL, Los Alamos, New Mexico 87545, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Kohama
authors.forename: A V
authors.initials: AV
authors.lastname: Sologubenko
authors.forename: N R
authors.initials: NR
authors.lastname: Dilley
authors.forename: V S
authors.initials: VS
authors.lastname: Zapf
authors.forename: M
authors.initials: M
authors.lastname: Jaime
authors.forename: J A
authors.initials: JA
authors.lastname: Mydosh
authors.forename: A
authors.initials: A
authors.lastname: Paduan-Filho
authors.forename: K A
authors.initials: KA
authors.lastname: Al-Hassanieh
authors.forename: P
authors.initials: P
authors.lastname: Sengupta
authors.forename: S
authors.initials: S
authors.lastname: Gangadharaiah
authors.forename: A L
authors.initials: AL
authors.lastname: Chernyshev
authors.forename: C D
authors.initials: CD
authors.lastname: Batista