Magnetic domain writing defined by electrical gating in Pt/Co film

Abstract

There is a need to control magnetic properties at a desired location in a magnetic film towards a realization of fundamental devices, such as domain wall logic or magnonic applications. Here, we demonstrate the formation of a magnetic domain structure at a desired location in a Pt/Co film, using electrical gating with a meshed gate electrode and sweeping the applied magnetic field. As the magnetic properties can be changed by modulating the electron density at the surface of the Co layer, this method in principle provides higher speed and power-efficient operation in inducing a nanoscale domain structure or in configuring a volatile magnonic crystal.

Magnetic Domains without Domain Walls: A Unique Effect of He+ Ion Bombardment in Ferrimagnetic Tb/Co Films

“…The subjects of our investigations are Tb/Co multilayers displaying, for small sublayer thicknesses, magnetic properties similar to amorphous Co-Tb alloy films [39][40][41][42][43]. In order to determine the influence of the 10 keV He + ion bombardment on the properties of the (Tb/Co) 6 multilayers as a function of the thickness ratio between Co and Tb layers, i.e. as a function of the effective multilayer composition a particular layer system was deposited.…”

“…Samples deposition. The (Tb-wedge 0-2nm/Co-0.66nm) 6 and (Tb-1.1nm/Co-0.66nm) 6 layered systems were deposited from elemental targets using magnetron sputtering in an ultra-high vacuum chamber (base pressure 10 −9 mbar) with an argon pressure of 10 −3 mbar on 20x20 mm 2 naturally oxidized Si(100) substrates coated with a Ti-4 nm/Au-30 nm buffer layer [39]. The wedge-shaped sublayers were produced using a linear shutter.…”

“…The ability to create lateral magnetic domain patterns is at the heart of a manifold of applications. Their use in magnetic mass memories [1][2][3][4] is absolutely straightforward but also in other areas, such as magnonics [5,6], or for the formation of defined domain patterns used for magnetophoresis in lab-on-a-chip devices [7][8][9][10][11] magnetic domain engineering forms a basic technology. For such applications, it is common to use ferromagnetic layers.…”

Voltage-induced coercivity change in Co film grown on Cr2O3 barrier

“…From this point, fcc-Co (111) or hcp-Co (0001) based materials are promising candidates, since a large interfacial PMA can easily be obtained for the Co (111) based multilayers. To date, several studies have reported on the electric field effect of Co (111) based multilayer systems, for example, electric field effect on Curie temperature of Co, 12) magnetic anisotropy of the induced moment of Pd in the Co/ Pd/MgO structure, [13][14][15][16] and magnetic anisotropy of Co in the Pt/Co/MgO structure, [17][18][19] SrTiO 3 /Co/Pt structure, 20) and Co/CoO/MgO oxidized interface. 21) A VCMA coefficient of up to 230 fJ V -1 m -1 has been reported at room temperature.…”

“…However, the large lattice mismatch between MgO (111) and Co (111) (corresponding to ∼18.6%) and the natural polar plane of MgO ((100) plane) prevent a highquality interface of Co (111)/MgO (111). MgO has been used in combination with other barriers such as HfO x 12,[16][17][18] to obtain sufficient insulation properties. For further investigation of the VCMA effect of Co (111), the development of new crystal dielectric barriers which realize a high-quality interface of Co (111)/dielectric barrier has been sought.…”