Origin of the Spin-Orbital Liquid State in a Nearly J=0 Iridate Ba3ZnIr2O9
2016 (English)In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 116, no 9, 097205Article in journal (Refereed) PublishedText
We show using detailed magnetic and thermodynamic studies and theoretical calculations that the ground state of Ba3ZnIr2O9 is a realization of a novel spin-orbital liquid state. Our results reveal that Ba3ZnIr2O9 with Ir5+ (5d(4)) ions and strong spin-orbit coupling (SOC) arrives very close to the elusive J = 0 state but each Ir ion still possesses a weak moment. Ab initio density functional calculations indicate that this moment is developed due to superexchange, mediated by a strong intradimer hopping mechanism. While the Ir spins within the structural Ir2O9 dimer are expected to form a spin-orbit singlet state (SOS) with no resultant moment, substantial frustration arising from interdimer exchange interactions induce quantum fluctuations in these possible SOS states favoring a spin-orbital liquid phase down to at least 100 mK.
Place, publisher, year, edition, pages
2016. Vol. 116, no 9, 097205
Physical Sciences Engineering and Technology
IdentifiersURN: urn:nbn:se:uu:diva-282812DOI: 10.1103/PhysRevLett.116.097205ISI: 000371419600016OAI: oai:DiVA.org:uu-282812DiVA: diva2:919094
FunderSwedish Research Council, INCA-2014-6426