Abstract
The magnetic behavior of a (BiFeO3)-Fe-57 powdered sample was studied at high pressures by the method of nuclear forward scattering (NFS) of synchrotron radiation. The NFS spectra from Fe-57 nuclei were recorded at room temperature under high pressures up to 61.4 GPa, which were created in a diamond anvil cell. In the pressure interval 0 < P < 47 GPa, the magnetic hyperfine field H-Fe at the Fe-57 nuclei increased reaching a value of similar to 52.5 T at 30 GPa, and then it slightly decreased to similar to 49.6 T at P = 47 GPa. As the pressure was increased further, the field H-Fe abruptly dropped to zero testifying a transition from the antiferromagnetic to a nonmagnetic state (magnetic collapse). In the pressure interval 47 < P < 61.4 GPa, the value of H-Fe remained zero. The field H-Fe recovered to the low-pressure values during decompression. (C) 2005 Pleiades Publishing, Inc.