Magnetic excitations in antiferromagnetically coupled superlattices: Fe/Mo and Fe/Cr

Low frequency magnetic response in antiferromagnetically coupled Fe/Cr multilayers.

The magnetic field and temperature dependence of the low frequency magnetic response of antiferromagnetically coupled Fe/Cr(100) multilayers has been studied between +/-500 Oe, from 2 to 300 K. At T = 2 K the losses exhibit an unusually strong frequency dependence which can be described within a single relaxation time scheme. This relaxation time proves to be strongly field dependent. These phe...

Evidence of long-wavelength collective excitations in magnetic superlattices.

We report on a mechanism of dynamic dipolar coupling in magnetic superlattices via long-wavelength nonevanescent fields. In the spin excitation spectra of our heterophase stripe structures, such interactions mediate a singlet<-->doublet crossover in the frequency regime driven by the orientation of an external static field. This crossover is a new feature observed in collective behavior of supe...

Spin waves in antiferromagnetically coupled bimetallic oxalates.

Bimetallic oxalates are molecule-based magnets with transition-metal ions M(II) and M(')(III) arranged on an open honeycomb lattice. Performing a Holstein-Primakoff expansion, we obtain the spin-wave spectrum of antiferromagnetically coupled bimetallic oxalates as a function of the crystal-field angular momentum L(2) and L(3) on the M(II) and M(')(III) sites. Our results are applied to the Fe(I...

PhD thesis booklet MAGNETIC PHASE AND DOMAIN EVOLUTION OF ANTIFERROMAGNETICALLY COUPLED MULTILAYERS

Low-frequency response in the magnetic susceptibility of antiferromagnetically coupled Fe/Cr multilayers

The magnetic field and temperature dependence of the low-frequency ( fo104 HzÞ inand out-of-phase magnetic response of antiferromagnetically coupled Fe/Cr(1 0 0) shows that at T > 100K both the real ðw0Þ and imaginary ðw00Þ parts of the susceptibility exhibit hysteretic dependence on the magnetic field with maxima of w00ðHÞ at HE725Oe. At T 1⁄4 2K the losses exhibit an unusual strong frequency ...