Spins in the vortices of a high-temperature superconductor.
Neutron scattering is used to characterize the magnetism of the vortices for the optimally doped high-temperature superconductor La(2-x)Sr(x)CuO4 (x = 0.163) in an applied magnetic field. As temperature is reduced, low-frequency spin fluctuations first disappear with the loss of vortex mobility, but then reappear. We find that the vortex state can be regarded as an inhomogeneous mixture of a superconducting spin fluid and a material containing a nearly ordered antiferromagnet. These experiments show that as for many other properties of cuprate superconductors, the important underlying microscopic forces are magnetic.
Lake
B
B
Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
Aeppli
G
G
Clausen
K N
KN
McMorrow
D F
DF
Lefmann
K
K
Hussey
N E
NE
Mangkorntong
N
N
Nohara
M
M
Takagi
H
H
Mason
T E
TE
Schröder
A
A