Controlled enhancement of spin-current emission by three-magnon splitting

Abstract

Spin currents--the flow of angular momentum without the simultaneous transfer of electrical charge--play an enabling role in the field of spintronics. Unlike the charge current, the spin current is not a conservative quantity within the conduction carrier system. This is due to the presence of the spin-orbit interaction that couples the spin of the carriers to angular momentum in the lattice. This spin-lattice coupling acts also as the source of damping in magnetic materials, where the precessing magnetic moment experiences a torque towards its equilibrium orientation; the excess angular momentum in the magnetic subsystem flows into the lattice. Here we show that this flow can be reversed by the three-magnon splitting process and experimentally achieve the enhancement of the spin current emitted by the interacting spin waves. This mechanism triggers angular momentum transfer from the lattice to the magnetic subsystem and modifies the spin-current emission. The finding illustrates the importance of magnon-magnon interactions for developing spin-current based electronics.

Roton-Phonon Interactions in SuperfluidHe4

“…The roton-phonon interaction does not give any observable roton linewidth. The present results show the importance of both cubic and quartic vertices in superfluid 4 He, and we expect that this will have a wide-ranging impact for Bose-condensed systems in general, covering areas such as excitons in semiconductors, magnon decay [20][21][22], non-linear effects in spintronics [23,24], and strongly interacting ultracold Bose gases [25].…”

Spin-Hall magnetoresistance in platinum on yttrium iron garnet: Dependence on platinum thickness and in-plane/out-of-plane magnetization

“…In summary, the SMR in Pt layers with different thicknesses [3,4,8, and 35 nm], deposited on top of YIG, was investigated for both in-plane and out-of-plane applied magnetic fields. In-plane magnetic field scans clearly show the presence of SMR for the transverse as well as the longitudinal configuration.…”

“…The ISHE has been used to detect, for example, spin pumping into Pt from various materials such as permalloy 2 (Py) and yttrium iron garnet (YIG). [3][4][5] For the opposite effect, to use Pt as a spin current injector, a charge current is sent through the Pt, creating a transverse spin accumulation by the spin-Hall effect (SHE). [6][7][8] Recently, Weiler et al 9 and Huang et al 10 observed magnetoresistance (MR) effects in Pt on YIG and related those effects to magnetic proximity.…”

“…In this paper, the angular dependence of the SMR in Pt on YIG is investigated for different Pt thicknesses (3,4,8, and 35 nm) and different deposition techniques (e-beam evaporation and dc sputtering), for applied in-plane as well as out-of-plane magnetic field sweeps, revealing the full magnetization behavior of the YIG. 17 All measurements are performed at room temperature.…”

Optimized Magneto-optical Isolator Designs Inspired by Seedlayer-Free Terbium Iron Garnets with Opposite Chirality

“…Improved crystallization of the garnet later yielded full mode conversion in 3mm 21 . Importantly, once highly gyrotropic YIG is grown successfully on Si, it may also find application in spintronics, for example, in spin logic and spin current generators 1,[34][35][36][37][38][39][40][41][42][43][44] . This paper will discuss the optical consequences of having seedlayers on waveguides with garnet claddings and will introduce two new garnet materials, terbium iron garnet (TIG, Tb 3 Fe 5 O 12 ) and bismuth-doped terbium iron garnet (Bi:TIG), both of which do not require seedlayers on Si or on other non-garnet substrates.…”