Coupling of spin and lattice modes in the S=1/2 two-dimensional antiferromagnet K2V3O8 with magneto-dielectric couplings

被引：12

作者：

Choi, K. -Y. ^{[1
]}

Lemmens, P. ^{[2
]}

Gnezdilov, V. P. ^{[3
]}

Sales, B. C. ^{[4
]}

Lumsden, M. D. ^{[4
]}

机构：

[1] Chung Ang Univ, Dept Phys, Seoul 156756, South Korea

[2] Tech Univ Carolo Wilhelmina Braunschweig, Inst Condensed Matter Phys, D-38106 Braunschweig, Germany

[3] BI Verkin Inst Low Temp Phys NASU, UA-61164 Kharkov, Ukraine

[4] Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA

来源：

PHYSICAL REVIEW B | 2012年 / 85卷 / 14期

关键词：

CRYSTAL-STRUCTURE; POLARIZATION; TEMPERATURE; SPECTRA;

D O I：

10.1103/PhysRevB.85.144434

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Lattice dynamics and magnetic excitations are investigated to elucidate the origin of magneto-dielectric effects in the S = 1/2 two-dimensional quantum spin compound K2V3O8. We find evidence for lattice instabilities at 110 K and 60 K as optical phonon anomalies and a soft mode at 26 cm(-1) in A(1) symmetry. Two-magnon excitations in B-1 symmetry show an unconventional double-peak structure and temperature dependence. This suggests the existence of a split mode near the zone boundary caused by a mixing of spin and lattice modes.

引用

页数：6

共 31 条

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