TY  - JOUR
AU  - Bera, A. K.
AU  - Lake, B.
AU  - Islam, A. T. M. N.
AU  - Schneidewind, A.
TI  - Critical properties of coupled anisotropic Haldane spin chains in a magnetic field
JO  - Physical review / B
VL  - 92
IS  - 6
SN  - 1098-0121
CY  - College Park, Md.
PB  - APS
M1  - FZJ-2015-05485
SP  - 060412
PY  - 2015
AB  - We use inelastic neutron scattering to measure magnetic fluctuations as a function of transverse magneticfield and temperature in a single crystal of the coupled Haldane chain compound SrNi2V2O8 with uniaxialanisotropy. At the base temperature (2 K), spin excitations confirm a field-induced quantum phase transitionfrom the disordered Haldane (gapped singlet) state to a gapped long-range ordered state through a quantumcritical point (QCP) (μ0Hc ≈ 11.5 T). At elevated temperatures in the vicinity of the QCP, both the energy andlinewidth of the lowest triplet mode scale linearly with temperature, in accordance with quantum criticality. Wealso demonstrate that the experimental field dependence of the triplet excitation modes at the base temperatureis in agreement with the bosonic and macroscopic models, but is in contrast to the fermionic and perturbativemodels.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000362207500002
DO  - DOI:10.1103/PhysRevB.92.060412
UR  - https://juser.fz-juelich.de/record/204893
ER  -