Pair correlations, short-range order, and dispersive excitations in the quasi-kagome quantum magnet volborthite
(2011) In Physical Review B (Condensed Matter and Materials Physics) 84(17).- Abstract
- We present spatial and dynamic information on the s = 1/2 distorted kagome antiferromagnet volborthite, Cu3V2O7(OD)(2) center dot 2D(2)O, obtained by polarized and inelastic neutron scattering. The instantaneous structure factor, S(Q), is dominated by nearest-neighbor pair correlations, with short-range order at wave vectors Q(1) = 0.65(3) angstrom(-1) and Q(2) = 1.15(5) angstrom(-1) emerging below 5 K. The excitation spectrum, S(Q,omega), reveals two steep branches dispersing from Q(1) and Q(2), and a flat mode omega(f) = 5.0(2) meV. The results allow us to identify the crossover at T* similar to 1 K in V-51 NMR and specific-heat measurements as the buildup of correlations at Q(1). We compare our data to theoretical models proposed for... (More)
- We present spatial and dynamic information on the s = 1/2 distorted kagome antiferromagnet volborthite, Cu3V2O7(OD)(2) center dot 2D(2)O, obtained by polarized and inelastic neutron scattering. The instantaneous structure factor, S(Q), is dominated by nearest-neighbor pair correlations, with short-range order at wave vectors Q(1) = 0.65(3) angstrom(-1) and Q(2) = 1.15(5) angstrom(-1) emerging below 5 K. The excitation spectrum, S(Q,omega), reveals two steep branches dispersing from Q(1) and Q(2), and a flat mode omega(f) = 5.0(2) meV. The results allow us to identify the crossover at T* similar to 1 K in V-51 NMR and specific-heat measurements as the buildup of correlations at Q(1). We compare our data to theoretical models proposed for volborthite, and also demonstrate that the excitation spectrum can be explained by spin-wave-like excitations with anisotropic exchange parameters, as suggested by recent local-density calculations. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/2253112
- author
- Nilsen, G. J. ; Coomer, F. C. ; de Vries, M. A. ; Stewart, J. R. ; Deen, Pascale LU ; Harrison, A. and Ronnow, H. M.
- organization
- publishing date
- 2011
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Physical Review B (Condensed Matter and Materials Physics)
- volume
- 84
- issue
- 17
- article number
- 172401
- publisher
- American Physical Society
- external identifiers
-
- wos:000296860400001
- scopus:82455181576
- ISSN
- 1098-0121
- DOI
- 10.1103/PhysRevB.84.172401
- language
- English
- LU publication?
- yes
- id
- e862fad7-4546-46e5-9a74-397ffa6277c8 (old id 2253112)
- date added to LUP
- 2016-04-01 13:56:32
- date last changed
- 2022-01-27 22:00:26
@article{e862fad7-4546-46e5-9a74-397ffa6277c8, abstract = {{We present spatial and dynamic information on the s = 1/2 distorted kagome antiferromagnet volborthite, Cu3V2O7(OD)(2) center dot 2D(2)O, obtained by polarized and inelastic neutron scattering. The instantaneous structure factor, S(Q), is dominated by nearest-neighbor pair correlations, with short-range order at wave vectors Q(1) = 0.65(3) angstrom(-1) and Q(2) = 1.15(5) angstrom(-1) emerging below 5 K. The excitation spectrum, S(Q,omega), reveals two steep branches dispersing from Q(1) and Q(2), and a flat mode omega(f) = 5.0(2) meV. The results allow us to identify the crossover at T* similar to 1 K in V-51 NMR and specific-heat measurements as the buildup of correlations at Q(1). We compare our data to theoretical models proposed for volborthite, and also demonstrate that the excitation spectrum can be explained by spin-wave-like excitations with anisotropic exchange parameters, as suggested by recent local-density calculations.}}, author = {{Nilsen, G. J. and Coomer, F. C. and de Vries, M. A. and Stewart, J. R. and Deen, Pascale and Harrison, A. and Ronnow, H. M.}}, issn = {{1098-0121}}, language = {{eng}}, number = {{17}}, publisher = {{American Physical Society}}, series = {{Physical Review B (Condensed Matter and Materials Physics)}}, title = {{Pair correlations, short-range order, and dispersive excitations in the quasi-kagome quantum magnet volborthite}}, url = {{http://dx.doi.org/10.1103/PhysRevB.84.172401}}, doi = {{10.1103/PhysRevB.84.172401}}, volume = {{84}}, year = {{2011}}, }