Mott-Anderson transition controlled by a magnetic field in pyrochlore molybdate.
The pyrochlore molybdate Gd2MO2O7 locates near the phase boundary between the ferromagnetic-metallic and the spin-glass insulating state. This metal-insulator transition is governed on a large energy scale by the electron-correlation effect, while the geometrical frustration causes the random potential. The magnetic field can tune the randomness of the potential and control, under a suitable pressure, the continuous Mott-Anderson transition precisely. The critical exponent (mu = 1.04 +/- 0.1) of the Mott-Anderson transition has been determined for this ferromagnetic orbital-degenerate electron system.
Hanasaki
N
N
Department of Applied Physics, University of Tokyo, Tokyo 113-8656, Japan.
Kinuhara
M
M
Kézsmárki
I
I
Iguchi
S
S
Miyasaka
S
S
Takeshita
N
N
Terakura
C
C
Takagi
H
H
Tokura
Y
Y