Thermally driven magnon valve with perpendicular magnetic anisotropy

Abstract

The active manipulation of quasiparticles, other than electrons, is a feasible alternative for developing the next generation of devices for information processing. Exploring magnons is advantageous as they can travel far and fast due to their low dissipation and high group velocity, transferring spin without charge transport, thus reducing the Joule heating. Moreover, magnon currents can switch a film's magnetization via a magnon torque facilitated by a perpendicular magnetic anisotropy (PMA). We demonstrate the proof of principle for three states' memories via transport studies of thermally excited magnon currents at room temperature in ferrimagnetic insulating magnon valves TmIG/Au/TmIG with PMA. While varying the relative TmIG magnetizations orientation, magnon currents excited in TmIG films are detected as a voltage in a top platinum electrode film due to the inverse spin Hall effect. The magnon transmission is maximum in the parallel state where the two signals sum up. Possibilities are seen for wave-based nonvolatile magneto-resistive random-access memory, sensing, and logic devices.

Role of two-dimensional monolayer MoS2 interlayer in the temperature-dependent longitudinal spin Seebeck effect in Pt/YIG bilayer structures

“…According to previous studies on magnon junction effect or magnon valve effect, the blocking effect of the ML MoS 2 layers can be related to the magnon blocking effect, because different layers show different magnetizations. [34][35][36] This is known as the magnon selection rule, in which spin-up lattices ([) can only accept right-circularly polarized magnons ([) and vice versa for spindown lattices (Y). 34,37 If the spacer has two spin-opposite lattices, then both right and le circularly polarized magnons can be accommodated.…”

From microelectronics to spintronics and magnonics

“…Analog to the spin valves whose resistance is high or low depending on their antiparallel or parallel magnetization states, respectively, these magnon valves/junctions can also output high or low magnon current in the SSE when magnetizations of the two magnetic insulators are aligned in parallel or antiparallel manner. This phenomenon is named as the magnon valve effect (MVE) [60,62] and magnon junction effect (MJE). [61,63] The involved physics is simple: the detected magnon current on the top MI is not only determined by the SSE of itself but also depends on the transmitted magnon current from the bottom MI.…”

Large-scale fabrication of thulium iron garnet film with perpendicular magnetic anisotropy using RF magnetron sputtering

“…Recently, thulium iron garnet (Tm 3 Fe 5 O 12 , TmIG) films have attracted considerable scientific attention. [1][2][3][4] TmIG has a negatively large magnetostriction constant of λ 111 = −5.2 × 10 −6 and the TmIG film on the gadolinium gallium garnet (Gd 3 Ga 5 O 12 , GGG) (111) substrate involves a strain of 0.49%, which induces perpendicular magnetic anisotropy (PMA) large enough to overcome the shape anisotropy. 5,6) The interfacial Dzyaloshinskii-Moriya interaction (DMI) properties of TmIG multilayers, which can stabilize domain walls and skyrmions, have been successfully identified by the emerging topological Hall effect.…”

“…[7][8][9][10][11][12][13] The observation of spin-orbit torque (SOT) switching 14,15) and skyrmion transport 7,16) on TmIG multilayers shows the potential for spin-orbitronic and skyrmionics devices. [1][2][3][4]17,18) The small damping stemming from the insulating nature of TmIG also allows for long-range propagation of spin waves. 19) The fabrication of TmIG films has been studied extensively using pulsed laser deposition (PLD) 5,[20][21][22] or off-axis sputtering.…”