Showing papers by "Andrii V. Chumak published in 2011"
TL;DR: It is experimentally show that exchange magnons can be detected by using a combination of spin pumping and the inverse spin-Hall effect proving its wavelength integrating capability down to the submicrometer scale.
Abstract: We experimentally show that exchange magnons can be detected by using a combination of spin pumping and the inverse spin-Hall effect proving its wavelength integrating capability down to the submicrometer scale. The magnons were injected in a ferrite yttrium iron garnet film by parametric pumping and the inverse spin-Hall effect voltage was detected in an attached Pt layer. The role of the density, wavelength, and spatial localization of the magnons for the spin pumping efficiency is revealed.
265 citations
TL;DR: In this article, a short spin-wave packet is excited in a yttrium-iron garnet (YIG) waveguide by a microwave signal and is detected at a distance of 3 mm by an attached Pt layer as a delayed spin Hall effect (ISHE) voltage pulse.
Abstract: Conversion of traveling magnons into an electron carried spin current is demonstrated in a time resolved experiment using a spatially separated inductive spin-wave source and an inverse spin Hall effect (ISHE) detector. A short spin-wave packet is excited in a yttrium-iron garnet (YIG) waveguide by a microwave signal and is detected at a distance of 3 mm by an attached Pt layer as a delayed ISHE voltage pulse. The delay in the detection appears due to the finite spin-wave group velocity and proves the magnon spin transport. The experiment suggests utilization of spin waves for the information transfer over macroscopic distances in spintronic devices and circuits.
110 citations
TL;DR: In this article, the authors measured the time decay of the magnetization of the arrays of Permalloy circular dots of submicron sizes near the vortex nucleation field and found that a considerable influence of external magnetic field and temperature on the slow magnetization dynamics was detected.
Abstract: Time decay of the magnetization of the arrays of Permalloy circular dots of submicron sizes was measured on a long time scale (hours) near the vortex nucleation field. A considerable influence of external magnetic field and temperature on the slow magnetization dynamics was detected. The observed effects are explained by overcoming the field dependent energy barriers in the process of vortex nucleation. The magnetic viscosity and energy barriers were found from the magnetization time decay dependencies.
15 citations
06 Jul 2011
TL;DR: In this article, the authors discuss how, by exploiting resonant spin-wave reflections from a magnonic crystal, an active ring system having a threshold mode with a well-defined and precisely predictable wavenumber may be realized.
Abstract: Spin-wave active rings–positive-feedback systems incorporating spin-wave waveguides–provide important insight into fundamental magnetics, enable experimental investigations into nonlinear wave phenomena, and potentially find application in microwave electronics. Such rings break into spontaneous, monomode oscillation at a certain threshold value of feedback gain. In general, the wavenumber of this initially excited, threshold mode is impossible to predict precisely. Here we discuss how, by exploiting resonant spin-wave reflections from a magnonic crystal, an active ring system having a threshold mode with a well-defined and precisely predictable wavenumber may be realized. Our work suggests that study and development of active ring systems incorporating magnonic crystals may deliver useful insight into spin-wave transmission in structured magnetic films as well as devices with technological applicability.
8 citations
06 Jul 2011
TL;DR: In this article, the authors describe an alternative approach in which spinmechatronic structures combining spin-wave transmission systems with magnetically loaded micro-and nano-mechanical elements provide spin-information processing functionality.
Abstract: Spin waves have long been recognized as potential signal carriers in spintronic devices. However, practical development of spin wave based information platforms is its infancy. To date, work in this area has focused on one-dimensional topologies based on purely magnetic thin-film transmission systems, typically exploiting interference phenomena to perform logical operations. In this paper, we describe an alternative approach in which spinmechatronic structures combining spin-wave transmission systems with magnetically loaded micro- and nano-mechanical elements provide spin-information processing functionality.
3 citations