Back to overview

Ba3MxTi3−xO9 (M = Ir, Rh): A family of 5d/4d-based diluted quantum spin liquids

Type of publication Peer-reviewed
Publikationsform Original article (peer-reviewed)
Author Kumar R., Sheptyakov Denis, Khuntia P., Rolfs Katharina, Freeman P. G., Rønnow Henrik, Tusharkanti Dey, Baenitz M., Mahajan A. V.,
Project Mott Physics Beyond the Heisenberg Model in Iridates and Related Materials
Show all

Original article (peer-reviewed)

Volume (Issue) 94
Page(s) 174410
Title of proceedings PHYSICAL REVIEW B
DOI 10.1103/physrevb.94.174410


We report the structural and magnetic properties of the 4d (M = Rh) based and 5d (M = Ir) based systems Ba3MxTi3−xO9 (nominally x = 0.5, 1). The studied compositions were found to crystallize in a hexagonal structure with the centrosymmetric space group P63/mmc. The structures comprise of A2O9 polyhedra [with the A site (possibly) statistically occupied by M and Ti] in which pairs of transition metal ions are stacked along the crystallographic c axis. These pairs form triangular bilayers in the ab plane. The magnetic Rh and Ir ions occupy these bilayers, diluted by Ti ions even for x = 1. These bilayers are separated by a triangular layer which is dominantly occupied by Ti ions. From magnetization measurements we infer strong antiferromagnetic couplings for all of the materials but the absence of any spin-freezing or spin-ordering down to 2 K. Further, specific heat measurements down to 0.35 K show no sign of a phase transition for any of the compounds. Based on these thermodynamic measurements we propose the emergence of a quantum spin liquid ground state for Ba3Rh0.5Ti2.5O9, and Ba3Ir0.5Ti2.5O9, in addition to the already reported Ba3IrTi2O9.