title: Chemical pressure induced spin freezing phase transition in kagome pr langasites.
abstract: The 2D kagome system Pr3Ga5SiO14 has been previously identified as a spin-liquid candidate in zero field, displaying no magnetic long-ranged order down to at least 35 mK. Perturbations upon such systems, either under applied fields or applied pressure, should induce a spin freezing phase transition, but there are very few experimental realizations of this phenomena other than the well-studied 3D pyrochlore Tb2Ti2O7. In this Letter, we report the observation of a spin freezing phase transition in Pr3Ga5SiO14 through the application of chemical pressure--that is, through a systematic substitution on the Si site with larger ions and an elongation of the nearest-neighbor Pr-Pr distance in the kagome lattice. This results in a suppression of the T2 component of the heat capacity, and the reduction of the exchange constant eventually leads to dipolar-driven spin freezing.
authors.affiliation: Department of Physics, Florida State University, Tallahassee, Florida 32306-3016, USA.
authors.forename: H D
authors.initials: HD
authors.lastname: Zhou
authors.forename: C R
authors.initials: CR
authors.lastname: Wiebe
authors.forename: Y-J
authors.initials: YJ
authors.lastname: Jo
authors.forename: L
authors.initials: L
authors.lastname: Balicas
authors.forename: R R
authors.initials: RR
authors.lastname: Urbano
authors.forename: L L
authors.initials: LL
authors.lastname: Lumata
authors.forename: J S
authors.initials: JS
authors.lastname: Brooks
authors.forename: P L
authors.initials: PL
authors.lastname: Kuhns
authors.forename: A P
authors.initials: AP
authors.lastname: Reyes
authors.forename: Y
authors.initials: Y
authors.lastname: Qiu
authors.forename: J R D
authors.initials: JR
authors.lastname: Copley
authors.forename: J S
authors.initials: JS
authors.lastname: Gardner