Pressure-driven collapse of the relativistic electronic ground state in a honeycomb

J. Patrick Clancy, Hlynur Gretarsson, Jennifer A. Sears, Yogesh Singh, Serge Desgreniers, Kavita Mehlawat, Samar Layek, Gregory Kh Rozenberg, Yang Ding, Mary H. Upton, Diego Casa, Ning Chen, Junhyuck Im, Yongjae Lee, Ravi Yadav, Liviu Hozoi, Dmitri Efremov, Jeroen Van Den Brink, Young June Kim

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

Honeycomb-lattice quantum magnets with strong spin-orbit coupling are promising candidates for realizing a Kitaev quantum spin liquid. Although iridate materials such as Li2IrO3 and Na2IrO3 have been extensively investigated in this context, there is still considerable debate as to whether a localized relativistic wavefunction (J eff = 1/2) provides a suitable description for the electronic ground state of these materials. To address this question, we have studied the evolution of the structural and electronic properties of α-Li2IrO3 as a function of applied hydrostatic pressure using a combination of X-ray diffraction and X-ray spectroscopy techniques. We observe striking changes even under the application of only small hydrostatic pressure (P ≤ 0.1 GPa): A distortion of the Ir honeycomb lattice (via X-ray diffraction), a dramatic decrease in the strength of spin-orbit coupling effects (via X-ray absorption spectroscopy), and a significant increase in non-cubic crystal electric field splitting (via resonant inelastic X-ray scattering). Our data indicate that α-Li2IrO3 is best described by a J eff = 1/2 state at ambient pressure, but demonstrate that this state is extremely fragile and collapses under the influence of applied pressure.

Original languageEnglish
Article number35
Journalnpj Quantum Materials
Volume3
Issue number1
DOIs
Publication statusPublished - 2018 Dec 1

Fingerprint

Hydrostatic pressure
Ground state
Orbits
X ray diffraction
Inelastic scattering
X ray absorption spectroscopy
ground state
Wave functions
X ray spectroscopy
X ray scattering
electronics
Crystal lattices
Electronic properties
Magnets
Structural properties
x rays
hydrostatic pressure
Electric fields
Crystals
Liquids

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Cite this

Clancy, J. P., Gretarsson, H., Sears, J. A., Singh, Y., Desgreniers, S., Mehlawat, K., ... Kim, Y. J. (2018). Pressure-driven collapse of the relativistic electronic ground state in a honeycomb. npj Quantum Materials, 3(1), [35]. https://doi.org/10.1038/s41535-018-0109-0
Clancy, J. Patrick ; Gretarsson, Hlynur ; Sears, Jennifer A. ; Singh, Yogesh ; Desgreniers, Serge ; Mehlawat, Kavita ; Layek, Samar ; Rozenberg, Gregory Kh ; Ding, Yang ; Upton, Mary H. ; Casa, Diego ; Chen, Ning ; Im, Junhyuck ; Lee, Yongjae ; Yadav, Ravi ; Hozoi, Liviu ; Efremov, Dmitri ; Van Den Brink, Jeroen ; Kim, Young June. / Pressure-driven collapse of the relativistic electronic ground state in a honeycomb. In: npj Quantum Materials. 2018 ; Vol. 3, No. 1.
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Clancy, JP, Gretarsson, H, Sears, JA, Singh, Y, Desgreniers, S, Mehlawat, K, Layek, S, Rozenberg, GK, Ding, Y, Upton, MH, Casa, D, Chen, N, Im, J, Lee, Y, Yadav, R, Hozoi, L, Efremov, D, Van Den Brink, J & Kim, YJ 2018, 'Pressure-driven collapse of the relativistic electronic ground state in a honeycomb', npj Quantum Materials, vol. 3, no. 1, 35. https://doi.org/10.1038/s41535-018-0109-0

Pressure-driven collapse of the relativistic electronic ground state in a honeycomb. / Clancy, J. Patrick; Gretarsson, Hlynur; Sears, Jennifer A.; Singh, Yogesh; Desgreniers, Serge; Mehlawat, Kavita; Layek, Samar; Rozenberg, Gregory Kh; Ding, Yang; Upton, Mary H.; Casa, Diego; Chen, Ning; Im, Junhyuck; Lee, Yongjae; Yadav, Ravi; Hozoi, Liviu; Efremov, Dmitri; Van Den Brink, Jeroen; Kim, Young June.

In: npj Quantum Materials, Vol. 3, No. 1, 35, 01.12.2018.

Research output: Contribution to journalArticle

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AU - Clancy, J. Patrick

AU - Gretarsson, Hlynur

AU - Sears, Jennifer A.

AU - Singh, Yogesh

AU - Desgreniers, Serge

AU - Mehlawat, Kavita

AU - Layek, Samar

AU - Rozenberg, Gregory Kh

AU - Ding, Yang

AU - Upton, Mary H.

AU - Casa, Diego

AU - Chen, Ning

AU - Im, Junhyuck

AU - Lee, Yongjae

AU - Yadav, Ravi

AU - Hozoi, Liviu

AU - Efremov, Dmitri

AU - Van Den Brink, Jeroen

AU - Kim, Young June

PY - 2018/12/1

Y1 - 2018/12/1

N2 - Honeycomb-lattice quantum magnets with strong spin-orbit coupling are promising candidates for realizing a Kitaev quantum spin liquid. Although iridate materials such as Li2IrO3 and Na2IrO3 have been extensively investigated in this context, there is still considerable debate as to whether a localized relativistic wavefunction (J eff = 1/2) provides a suitable description for the electronic ground state of these materials. To address this question, we have studied the evolution of the structural and electronic properties of α-Li2IrO3 as a function of applied hydrostatic pressure using a combination of X-ray diffraction and X-ray spectroscopy techniques. We observe striking changes even under the application of only small hydrostatic pressure (P ≤ 0.1 GPa): A distortion of the Ir honeycomb lattice (via X-ray diffraction), a dramatic decrease in the strength of spin-orbit coupling effects (via X-ray absorption spectroscopy), and a significant increase in non-cubic crystal electric field splitting (via resonant inelastic X-ray scattering). Our data indicate that α-Li2IrO3 is best described by a J eff = 1/2 state at ambient pressure, but demonstrate that this state is extremely fragile and collapses under the influence of applied pressure.

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Clancy JP, Gretarsson H, Sears JA, Singh Y, Desgreniers S, Mehlawat K et al. Pressure-driven collapse of the relativistic electronic ground state in a honeycomb. npj Quantum Materials. 2018 Dec 1;3(1). 35. https://doi.org/10.1038/s41535-018-0109-0