Publication Type
Journal
Journal Name
Physical Review Letters
Publication Date
Page Number
167202
Volume
98
Issue
16
Abstract
The weakly coupled quasi-one-dimensional spin ladder compound CH32HHNH3CuCl3 is studied by
neutron scattering in magnetic fields exceeding the critical field of Bose-Einstein condensation of
magnons. Commensurate long-range order and the associated Goldstone mode are detected and found
to be similar to those in reference to spin-dimer materials. However, for the upper two massive magnon
branches, the observed behavior is totally different, culminating in a drastic collapse of excitation
bandwidth beyond the transition point.
