Excitations from a Bose-Einstein condensate of magnons in coupled spin ladders.
نویسندگان
چکیده
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.
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عنوان ژورنال:
- Physical review letters
دوره 98 16 شماره
صفحات -
تاریخ انتشار 2007