Accurate measurement of domain wall velocity in amorphous microwires, submicron wires, and nanowires

Abstract

A new method for measuring the domain wall velocity in a single, ultrathin ferromagnetic amorphous wire with the diameter down to 100 nm is presented. The method has been developed in order to increase the sensitivity in studying the domain wall propagation in bistable magnetic wires in a wide range of field amplitudes, with much larger values of the applied field as compared to those employed when studying the wall propagation in typical amorphous microwires. The large fields required to propagate the domain walls in ultrathin wires are able to nucleate new domain walls in the samples and, therefore, they can affect the accuracy of the entire measurement. The proposed experimental setup prevents such situations by using a number of complex pick-up coils, which allow the detection of the direction of the wall propagation along with the precise measurement of the domain wall velocity. The newly developed method is especially important now, when large effort is devoted to the development of domain wall logic devices based on ultrathin magnetic wires and nanowires.

Influence of cold drawing on the magnetic properties and giant magneto-impedance response of FINEMET nanocrystalline wires

“…6 The GMI response was measured using an impedance-meter, in the frequency range of 10-250 MHz. Magnetostriction was measured by the Small Angle Magnetization Rotation (SAMR) method.…”

Ultrathin Nanocrystalline Magnetic Wires

“…In order to easily detect the direction The domain wall velocity has been measured using an improved Sixtus-Tonks technique, with four pick-up coils, to allow the detection of walls with any additionally nucleated domains that could alter the precision of the measurements. This method has been refined in order to adapt it for the very small transverse dimensions of the nanowires and submicron wires [35]. Figure 3 shows a schematic of the system developed for the domain wall velocity measurements in the amorphous glass-coated nanowires and submicron wires.…”

High domain wall velocities in in-plane magnetized (Ga,Mn)(As,P) layers

“…Inside the cryostat, a homemade set of micro-coils was designed to apply in-plane pulsed fields H pul of up to 42 mT (risetime 100 ns). Contrary to most DW propagation studies relying on transport measurements 11,19 , this set-up permits the simultaneous imaging of the propagating domains with a large field of view and application of short field pulses (see Ref. 16 for experimental details).…”