Possible Quantum Paramagnetism in Compressed Sr2IrO4

Haskel, D.; Fabbris, G.; Kim, J. H.; Veiga, L. S.  I.; Mardegan, J. R.  L.; Escanhoela, C. A.; Chikara, S.; Struzhkin, V.; Senthil, T.; Kim, B. J.; Cao, G.; Kim, J. -W.

doi:10.1103/PhysRevLett.124.067201

Title: Possible Quantum Paramagnetism in Compressed ${Sr}_{2} {IrO}_{4}$

Journal Article · 11 February 2020 · Physical Review Letters

DOI: https://doi.org/10.1103/PhysRevLett.124.067201 · OSTI ID:1607469

^[1];

^[1]; Kim, J. H. ^[1]; Veiga, L. S. I. ^[2]; Mardegan, J. R. L. ^[3]; Escanhoela, C. A. ^[4];

^[1]; Struzhkin, V. ^[5]; Senthil, T. ^[6]; Kim, B. J. ^[7]; Cao, G. ^[8]; Kim, J. -W. ^[1]

Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS); Brazilian Synchrotron Light Lab. (LNLS), Campinas, SP (Brazil); Univ. of Campinas (UNICAMP), Sao Paulo (Brazil). Instituto de Física Gleb Wataghin; Univ. College London, Bloomsbury (United Kingdom). London Centre for Nanotechnology and Dept. of Physics and Astronomy
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS); Univ. of Campinas (UNICAMP), Sao Paulo (Brazil). Instituto de Física Gleb Wataghin
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS); Brazilian Synchrotron Light Lab. (LNLS), Campinas, SP (Brazil)
Carnegie Inst. of Science, Washington, DC (United States). Geophysical Lab.
Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Dept. of Physics
Inst. for Basic Science (IBS), Pohang (South Korea). Center for Artificial Low Dimensional Electronic Systems; Pohang Univ. of Science and Technology (South Korea)
Univ. of Colorado, Boulder, CO (United States). Dept. of Physics

The result of compression on the magnetic ground state of ${Sr}_{2} {IrO}_{4}$ is studied with x-ray resonant techniques in the diamond anvil cell. The weak interlayer exchange coupling between square-planar 2D ${IrO}_{2}$ layers is easily modified upon compression, with a crossover between magnetic structures around 7 GPa mimicking the effect of an applied magnetic field at ambient pressure. Higher pressures drive an order-disorder magnetic phase transition with no magnetic order detected above 17–20 GPa. The persistence of strong exchange interactions between $J_{eff} = 1 / 2$ magnetic moments within the insulating ${IrO}_{2}$ layers up to at least 35 GPa points to a highly frustrated magnetic state in compressed ${Sr}_{2} {IrO}_{4}$ , opening the door for realization of novel quantum paramagnetic phases driven by extended $5 d$ orbitals with entangled spin and orbital degrees of freedom.

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Research Organization:: Argonne National Laboratory (ANL), Argonne, IL (United States)

Sponsoring Organization:: USDOE Office of Science (SC), Basic Energy Sciences (BES); National Science Foundation (NSF)

Grant/Contract Number:: AC02-06CH11357; DMR-1712101; DMR-1903888; IBS-R014-A2

OSTI ID:: 1607469

Alternate ID(s):: OSTI ID: 1599480

Journal Information:: Physical Review Letters, Vol. 124, Issue 6; ISSN 0031-9007

Publisher:: American Physical Society (APS)Copyright Statement

Country of Publication:: United States

Language:: English

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Cited by: 18 works

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