Magnons and continua in a magnetized and dimerized spin- 12 chain

M. B. Stone; Y. Chen; D. H. Reich; C. Broholm; G. Xu; J. R.D. Copley; J. C. Cook

doi:10.1103/PhysRevB.90.094419

Magnons and continua in a magnetized and dimerized spin- 12 chain

M. B. Stone
, Y. Chen
, D. H. Reich
, C. Broholm
, G. Xu
, J. R.D. Copley
, J. C. Cook

Research output: Contribution to journal › Article › peer-review

10 Scopus citations

Abstract

We examine the magnetic field dependent excitations of the dimerized spin-1/2 chain, copper nitrate, with antiferromagnetic intradimer exchange J1=0.44(1)meV and exchange alternation α=J2/J1=0.26(2). Magnetic excitations in three distinct regimes of magnetization are probed through inelastic neutron scattering at low temperatures. At low and high fields there are three and two long-lived magnonlike modes, respectively. The number of modes and the antiphase relationship between the wave-vector dependent energy and intensity of magnon scattering reflect the distinct ground states: A singlet ground state at low fields μ0H<μ0Hc1=2.8T and an Sz=1/2 product state at high fields μ0H>μ0Hc2=4.2T. In the intermediate-field regime, a continuum of scattering for â.,ω≈J1 is indicative of a strongly correlated gapless quantum state without coherent magnons.

Original language	English
Article number	094419
Journal	Physical Review B - Condensed Matter and Materials Physics
Volume	90
Issue number	9
DOIs	https://doi.org/10.1103/PhysRevB.90.094419
State	Published - Sep 29 2014

Access to Document

10.1103/PhysRevB.90.094419

Cite this

@article{05742c6ed6514117b13eee89ac183b8a,

title = "Magnons and continua in a magnetized and dimerized spin- 12 chain",

abstract = "We examine the magnetic field dependent excitations of the dimerized spin-1/2 chain, copper nitrate, with antiferromagnetic intradimer exchange J1=0.44(1)meV and exchange alternation α=J2/J1=0.26(2). Magnetic excitations in three distinct regimes of magnetization are probed through inelastic neutron scattering at low temperatures. At low and high fields there are three and two long-lived magnonlike modes, respectively. The number of modes and the antiphase relationship between the wave-vector dependent energy and intensity of magnon scattering reflect the distinct ground states: A singlet ground state at low fields μ0H<μ0Hc1=2.8T and an Sz=1/2 product state at high fields μ0H>μ0Hc2=4.2T. In the intermediate-field regime, a continuum of scattering for {\^a}.,ω≈J1 is indicative of a strongly correlated gapless quantum state without coherent magnons.",

author = "Stone, \{M. B.\} and Y. Chen and Reich, \{D. H.\} and C. Broholm and G. Xu and Copley, \{J. R.D.\} and Cook, \{J. C.\}",

note = "Publisher Copyright: {\textcopyright} 2014 American Physical Society.",

year = "2014",

month = sep,

day = "29",

doi = "10.1103/PhysRevB.90.094419",

language = "English",

volume = "90",

journal = "Physical Review B - Condensed Matter and Materials Physics",

issn = "1098-0121",

publisher = "American Physical Society",

number = "9",

}

TY - JOUR

T1 - Magnons and continua in a magnetized and dimerized spin- 12 chain

AU - Stone, M. B.

AU - Chen, Y.

AU - Reich, D. H.

AU - Broholm, C.

AU - Xu, G.

AU - Copley, J. R.D.

AU - Cook, J. C.

PY - 2014/9/29

Y1 - 2014/9/29

N2 - We examine the magnetic field dependent excitations of the dimerized spin-1/2 chain, copper nitrate, with antiferromagnetic intradimer exchange J1=0.44(1)meV and exchange alternation α=J2/J1=0.26(2). Magnetic excitations in three distinct regimes of magnetization are probed through inelastic neutron scattering at low temperatures. At low and high fields there are three and two long-lived magnonlike modes, respectively. The number of modes and the antiphase relationship between the wave-vector dependent energy and intensity of magnon scattering reflect the distinct ground states: A singlet ground state at low fields μ0H<μ0Hc1=2.8T and an Sz=1/2 product state at high fields μ0H>μ0Hc2=4.2T. In the intermediate-field regime, a continuum of scattering for â.,ω≈J1 is indicative of a strongly correlated gapless quantum state without coherent magnons.

AB - We examine the magnetic field dependent excitations of the dimerized spin-1/2 chain, copper nitrate, with antiferromagnetic intradimer exchange J1=0.44(1)meV and exchange alternation α=J2/J1=0.26(2). Magnetic excitations in three distinct regimes of magnetization are probed through inelastic neutron scattering at low temperatures. At low and high fields there are three and two long-lived magnonlike modes, respectively. The number of modes and the antiphase relationship between the wave-vector dependent energy and intensity of magnon scattering reflect the distinct ground states: A singlet ground state at low fields μ0H<μ0Hc1=2.8T and an Sz=1/2 product state at high fields μ0H>μ0Hc2=4.2T. In the intermediate-field regime, a continuum of scattering for â.,ω≈J1 is indicative of a strongly correlated gapless quantum state without coherent magnons.

UR - https://www.scopus.com/pages/publications/84907459232

U2 - 10.1103/PhysRevB.90.094419

DO - 10.1103/PhysRevB.90.094419

M3 - Article

AN - SCOPUS:84907459232

SN - 1098-0121

VL - 90

JO - Physical Review B - Condensed Matter and Materials Physics

JF - Physical Review B - Condensed Matter and Materials Physics

IS - 9

M1 - 094419

ER -

Magnons and continua in a magnetized and dimerized spin- 12 chain

Abstract

Access to Document

Other files and links

Fingerprint

Cite this