Evidence for a magnetic-polaron state in the low-carrier system CeP

Elastic neutron-scattering experiments performed in the low-carrier system CeP show interesting magnetic diffraction patterns under a magnetic field. They can be explained by the stacking of the ferromagnetically coupled ${\mathrm{\Gamma }}_8$ double Ce layers among the antiferromagnetically coupled ${\mathrm{\Gamma }}_7$ layers with a period of eleven Ce layers along the field direction, even though the crystal-field level energy of ${\mathrm{\Gamma }}_8$ is 160 K. The result gives direct evidence for the existence of the magnetic-polaron state in CeP proposed by Kasuya et al.