Large Spin-Wave Energy Gap in the Bilayer Iridate Sr3Ir2O7: Evidence for Enhanced Dipolar Interactions Near the Mott Metal-Insulator Transition

被引：131

作者：

Kim, Jungho ^{[1
]}

Said, A. H. ^{[1
]}

Casa, D. ^{[1
]}

Upton, M. H. ^{[1
]}

Gog, T. ^{[1
]}

Daghofer, M. ^{[2
]}

Jackeli, G. ^{[3
]}

van den Brink, J. ^{[2
]}

Khaliullin, G. ^{[3
]}

Kim, B. J. ^{[4
]}

机构：

[1] Argonne Natl Lab, Adv Photon Source, Argonne, IL 60439 USA

[2] IFW Dresden, Inst Theoret Solid Sate Phys, D-01069 Dresden, Germany

[3] Max Planck Inst Solid State Res, D-70569 Stuttgart, Germany

[4] Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA

来源：

PHYSICAL REVIEW LETTERS | 2012年 / 109卷 / 15期

关键词：

Semiconductor insulator boundaries - X ray scattering - Mott insulators - Wave energy conversion - Metal insulator boundaries;

D O I：

10.1103/PhysRevLett.109.157402

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

Using resonant inelastic x-ray scattering, we observe in the bilayer iridate Sr3Ir2O7, a spin-orbit coupling driven magnetic insulator with a small charge gap, a magnon gap of approximate to 92 meV for both acoustic and optical branches. This exceptionally large magnon gap exceeds the total magnon bandwidth of approximate to 70 meV and implies a marked departure from the Heisenberg model, in stark contrast to the case of the single-layer iridate Sr2IrO4. Analyzing the origin of these observations, we find that the giant magnon gap results from bond-directional pseudodipolar interactions that are strongly enhanced near the metal-insulator transition boundary. This suggests that novel magnetism, such as that inspired by the Kitaev model built on the pseudodipolar interactions, may emerge in small charge-gap iridates.

引用

页数：5

共 30 条

[1] Resonant inelastic x-ray scattering studies of elementary excitations [J].

Ament, Luuk J. P. ;

van Veenendaal, Michel ;

Devereaux, Thomas P. ;

Hill, John P. ;

van den Brink, Jeroen .

REVIEWS OF MODERN PHYSICS, 2011, 83 (02) :705-767

[2] LMM AUGER-SPECTRA OF CU, ZN, GA, AND GE .1. TRANSITION-PROBABILITIES, TERM SPLITTINGS, AND EFFECTIVE COULOMB INTERACTION [J].

ANTONIDES, E ;

JANSE, EC ;

SAWATZKY, GA .

PHYSICAL REVIEW B, 1977, 15 (04) :1669-1679

[3]

Bosch A., 1980, SOLID STATE COMMUN, V34, P141

[4] On the magnetic structure of Sr3Ir2O7: an x-ray resonant scattering study [J].

Boseggia, S. ;

Springell, R. ;

Walker, H. C. ;

Boothroyd, A. T. ;

Prabhakaran, D. ;

Collins, S. P. ;

McMorrow, D. F. .

JOURNAL OF PHYSICS-CONDENSED MATTER, 2012, 24 (31)

[5] Antiferromagnetic order and domains in Sr3Ir2O7 probed by x-ray resonant scattering [J].

Boseggia, S. ;

Springell, R. ;

Walker, H. C. ;

Boothroyd, A. T. ;

Prabhakaran, D. ;

Wermeille, D. ;

Bouchenoire, L. ;

Collins, S. P. ;

McMorrow, D. F. .

PHYSICAL REVIEW B, 2012, 85 (18)

[6] Magnetically Driven Metal-Insulator Transition in NaOsO3 [J].

Calder, S. ;

Garlea, V. O. ;

McMorrow, D. F. ;

Lumsden, M. D. ;

Stone, M. B. ;

Lang, J. C. ;

Kim, J. -W. ;

Schlueter, J. A. ;

Shi, Y. G. ;

Yamaura, K. ;

Sun, Y. S. ;

Tsujimoto, Y. ;

Christianson, A. D. .

PHYSICAL REVIEW LETTERS, 2012, 108 (25)

[7] Anomalous magnetic and transport behavior in the magnetic insulator Sr3Ir2O7 -: art. no. 214412 [J].

Cao, G ;

Xin, Y ;

Alexander, CS ;

Crow, JE ;

Schlottmann, P ;

Crawford, MK ;

Harlow, RL ;

Marshall, W .

PHYSICAL REVIEW B, 2002, 66 (21) :1-7

[8] Kitaev-Heisenberg Model on a Honeycomb Lattice: Possible Exotic Phases in Iridium Oxides A2IrO3 [J].

Chaloupka, Jiri ;

Jackeli, George ;

Khaliullin, Giniyat .

PHYSICAL REVIEW LETTERS, 2010, 105 (02)

[9] Spin Waves and Revised Crystal Structure of Honeycomb Iridate Na2IrO3 [J].

Choi, S. K. ;

Coldea, R. ;

Kolmogorov, A. N. ;

Lancaster, T. ;

Mazin, I. I. ;

Blundell, S. J. ;

Radaelli, P. G. ;

Singh, Yogesh ;

Gegenwart, P. ;

Choi, K. R. ;

Cheong, S. -W. ;

Baker, P. J. ;

Stock, C. ;

Taylor, J. .

PHYSICAL REVIEW LETTERS, 2012, 108 (12)

[10]

Clancy J. P., ARXIV12070960

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