Excitations from a Bose-Einstein condensate of magnons in coupled spin ladders.
The weakly coupled quasi-one-dimensional spin ladder compound (CH3)2CHNH3CuCl3 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.
Garlea
V O
VO
Neutron Scattering Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6393, USA.
Zheludev
A
A
Masuda
T
T
Manaka
H
H
Regnault
L-P
LP
Ressouche
E
E
Grenier
B
B
Chung
J-H
JH
Qiu
Y
Y
Habicht
K
K
Kiefer
K
K
Boehm
M
M