Ferromagnetic resonance in copper-permalloy point contacts
2014 (English)In: Fizika Nizkih Temperatur, ISSN 0132-6414, E-ISSN 1816-0328, Vol. 40, no 10, 1187-1197 p.Article in journal (Refereed) Published
The systematic investigations of the response signal of Copper-Permalloy (Ni80Fe20) point contacts to microwave irradiation (8-12 GHz) are performed. The influence of external magnetic field strength, transport current flowing through the contact, the intensity and frequency of the RF exposure on the measured signal is studied. The contributions to the contacts resistance from the effects of giant and anisotropic magnetoresistance are analyzed. It is established experimentally that the position of resonance features is in good agreement with the Kittel formula calculation for FMR in the film at a parallel H field. The resonance signal was observed on the background of an additional contribution due to the rectification of RF current on the nonlinear contact IV-curve. It is found that there are two mechanisms for the resonant response are revealed: a synchronous self-detection by means of mixing of RF current with temporal variations of resistance and a bolometric mechanism associated with a steady-state change of contact resistance under excitation of magnetization precession (a bolometric response). It is found that the resonance signal amplitude is linearly proportional to transport current through the contact and microwave irradiation intensity.
Place, publisher, year, edition, pages
2014. Vol. 40, no 10, 1187-1197 p.
Anisotropic magnetoresistance, Microwave irradiation, Point contact, Spin valve, Spin-transfer torque
IdentifiersURN: urn:nbn:se:kth:diva-161669ScopusID: 2-s2.0-84907272572OAI: oai:DiVA.org:kth-161669DiVA: diva2:804965
QC 201504142015-04-142015-03-132015-04-14Bibliographically approved