Spin dynamics in point contacts to single ferromagnetic films

• Excitation of magnons or spin waves driven by nominally unpolarized transport currents in point contacts of normal and ferromagnetic metals is probed by irradiating the contacts with microwaves. Two characteristic dynamic effects are observed: a suppression of spin-wave nonlinearities in the point contact conductance by off-resonance microwave irradiation and a resonant stimulation of spin-wave peaks in the differential resistance of the nanocontacts by the microwave field. These observations provide direct evidence that the magnetoresistance peaks observed are due to gigahertz spin dynamics at the ferromagnetic interface driven by the spin transfer torque effect of the transport current.

Ämnesord

NATURVETENSKAP  -- Fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences (hsv//eng)

Nyckelord

cobalt; copper; ferromagnetic materials; magnetic thin films; magnetoresistance; magnons; metallic thin films; nanocontacts; point contacts; radiation effects; spin dynamics; spin polarised transport; spin waves

Physics

Fysik

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)