Confinement of spin density waves in Cr films

ENRIQUE KAUL; LEANDRO TOSI; HERNAN PASTORIZA; EDUARDO OSQUIGUIL

Gramado, Rio Grande do Sul

Encuentro; X Encontro Anual da Sociedade Brasileira de Pesquisa em Materiais (SBPMat); 2011

We measured the electrical resistivity, ρ, of epitaxial Cr films of different thicknesses grown on MgO (100) substrates, as a function of temperature, T, and magnetic field, H. Our results show a hysteretic behavior of ρ(T) for certain thicknesses that is robust even in magnetic fields as high as 16T. This may be explained by the confinement of quantized spin density waves in the film thickness. We experimentally show that the amplitude of the hysteresis as a function of film thickness, which is related to the energy difference between a spin density wave with N or N+1 nodes, strongly depends on the boundary conditions at the Cr interfaces.