Cooperative ordering of gapped and gapless spin networks in Cu2Fe2Ge4O13.
The unusual magnetic properties of a novel low-dimensional quantum ferrimagnet Cu2Fe2Ge4O13 are studied using bulk methods, neutron diffraction, and inelastic neutron scattering. It is shown that this material can be described in terms of two low-dimensional quantum spin subsystems, one gapped and the other gapless, characterized by two distinct energy scales. Long-range magnetic ordering observed at low temperatures is a cooperative phenomenon caused by weak coupling of these two spin networks.
Masuda
T
T
Condensed Matter Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831-6393, USA. masudat@ornl.gov
Zheludev
A
A
Grenier
B
B
Imai
S
S
Uchinokura
K
K
Ressouche
E
E
Park
S
S