Interfacial contribution to thickness dependent in-plane anisotropic magnetoresistance

Abstract

We have studied in-plane anisotropic magnetoresistance (AMR) in cobalt films with overlayers having designed electrically interface transparency. With an electrically opaque cobalt/overlayer interface, the AMR ratio is shown to vary in inverse proportion to the cobalt film thickness; an indication that in-plane AMR is a consequence of anisotropic scattering with both volume and interfacial contributions. The interface scattering anisotropy opposes the volume scattering contribution, causing the AMR ratio to diminish as the cobalt film thickness is reduced. An intrinsic interface effect explains the significantly reduced AMR ratio in ultra-thin films.

Manipulation of Magnetic Properties and Magnetoresistance in Co/Cu/γ′-Fe4N/Mica Flexible Spin Valves via External Mechanical Strains

“…The positive MR of Co(2.4)/Cu(7.5)/γ′-Fe 4 N­(7.9) flexible SPVs with H in‑plane ∥ I , H in‑plane ⊥ I , and H out‑of‑plane ⊥ I configurations indicates that the AMR effect vanishes. A similar phenomenon was also noted by Tokaç et al, and they pointed out that interface scattering is gradually obvious with the reduction of the FM thickness and the AMR effect vanishes at a critical thickness . The asymmetrical MR behavior of Co(2.4)/Cu(7.5)/γ′-Fe 4 N­(7.9) flexible SPVs is attributed to the exchange bias effect due to the absence of a capping layer or a rough Co/Cu interface.…”

“…62 A similar phenomenon was also noted by Tokaçet al, and they pointed out that interface scattering is gradually obvious with the reduction of the FM thickness and the AMR effect vanishes at a critical thickness. 63 The asymmetrical MR behavior of Co(2.4)/Cu(7.5)/γ′-Fe 4 N(7.9) flexible SPVs is attributed to the exchange bias effect due to the absence of a capping layer or a rough Co/Cu interface. Figure S4 shows the M−H curves of Co(2.4)/Cu(7.5)/γ′-Fe 4 N(7.9) flexible SPVs at 50 K, where a ±5 T cooling field was added to freeze.…”

Effects of transition metal spacers on spin-orbit torques, spin Hall magnetoresistance, and magnetic anisotropy of Pt/Co bilayers

“…Interfaces play a crucial role in determining the strength and symmetries of SOTs 7,9-11 , as well as other interface-related spin transport and dynamic effects such as the spin Hall 12 and Rashba-Edelstein magnetoresistance 13 , unidirectional magnetoresistance [14][15][16][17][18][19][20] , spin Seebeck effect 21 , spin-torque ferromagnetic resonance 22 , and spin pumping [23][24][25] . Additionally, interfaces in thin film structures play a dominant role in many other magnetic and electrical properties such as perpendicular magnetic anisotropy [26][27][28][29][30] , proximity magnetism [30][31][32][33] , anisotropic magnetoresistance [34][35][36][37] , and anomalous Hall effect [38][39][40][41][42][43] .The damping-like (DL) and field-like (FL) SOT are manifestations of the spin accumulation generated by an in-plane charge current flowing through HM/FM bilayers 9,[44][45][46] . The most widely used HM layers are 5d elements such as Pt, Ta or W (Refs.…”

Magnetic and Electrical Properties of Electrodeposited Nickel Films

“…Magneto-Resistance (MR) setup is a powerful system adopted by many investigators to gain insight into the magnetic and electrical transport properties of ferromagnetic thin films (Alcer and Atkinson, 2017;Tokaç, et al, 2015), individual rectangular nanowires (Fernández-Pacheco, et al, 2008;Oliveira, et al, 2010;Azevedo, 2008 Tokaç, et al, 2015), rod nanowires embedded in their membranes (Fert and Piraux, 1999;Ferré, et al, 1997;Pignard, et al, 2000), and isolated rod wires (Rheem, 2007a;2007b;2007c;2007d;Sultan, 2017) using the Anisotropic Magneto Resistance (AMR) effect. This is due to the sensitivity of AMR to the relative direction of the magnetic spins within the bulk of such materials with respect to the applied electrical current.…”