The effect of edge-roughness of magnetic nanowires on the degree of asymmetry in transverse domain walls

Abstract

The effect of edge roughness of permalloy nanowires can be quantified through the measurement of asymmetry in transverse domain walls.

Field-driven single domain wall motion in ferromagnetic nanowires

“…The 20 nm-thick DWT structures studied here were fabricated with two main steps: (1) a continuous 20 nm-thick Py lm was evaporated onto an electron transparent TEM membrane using a thermal evaporator with the evaporation rate of 0.03 nm s À1 . 29,30 The TEM membrane is a 35 nm-thick amorphous Si 3 N 4 lm supported on a 500 mm-thick silicon frame with a 100 Â 100 mm 2 electron transparent window, obtained from TED PELLA, INC. The lm thickness was controlled and monitored using a quartz crystal microbalance technique where a correlation between mechanical oscillation and resonant frequency is monitored.…”

“…23 (2) The DWT structures with different geometries, as shown in subsections 2.1 and 4.4, were patterned using the EBL and focused-ion beam (FIB) techniques. 21,[29][30][31][32][33] These facilities are available in the James Watt and Kelvin nanofabrication and characterization centres at University of Glasgow. Using these fabrication methods, those designed structures were isolated from the continuous lms.…”

“…Using these fabrication methods, those designed structures were isolated from the continuous lms. 21,29 The magnetic characterization was performed using the Fresnel imaging mode of the FEG-TEM Philips CM20 with a defocus distance of 3.6 mm. 29 To avoid charging during the EBL/FIB fabrication and TEM imaging, a very thin conducting Au layer of 10 nm was deposited in the backside of the TEM-Si 3 N 4 membrane using a sputtering deposition.…”

“…21,29 The magnetic characterization was performed using the Fresnel imaging mode of the FEG-TEM Philips CM20 with a defocus distance of 3.6 mm. 29 To avoid charging during the EBL/FIB fabrication and TEM imaging, a very thin conducting Au layer of 10 nm was deposited in the backside of the TEM-Si 3 N 4 membrane using a sputtering deposition. With the use of the EBL method, edge roughness behaviour of these DWT structures slightly improve as compared to that of structures fabricated by the FIB milling technique, this was partially discussed in other works.…”

Domain Wall Injection in Spin Valve Systems with Reservoirs of Different Geometries

“…The pad possessed a lower coercivity than the nanostrip due to the high anisotropy of the latter, and changes in the magnetization distribution of the pad resulted in the creation of a wall in the vicinity of the pad/nanostrip junction. DW is nucleated at smaller fields in the nucleation elliptical pad, whereas much larger fields are required for DWs to be injected into the nanostrip itself [12]. Fabricated elliptical pads are used to obtain vortex domain walls and investigate the domain wall injection process.…”