Antiferromagnetic domain wall engineering in chromium films

Abstract

We have engineered an antiferromagnetic domain wall by utilizing a magnetic frustration effect of a thin iron cap layer deposited on a chromium film. Through lithography and wet etching we selectively remove areas of the Fe cap layer to form a patterned ferromagnetic mask over the Cr film. Removing the Fe locally removes magnetic frustration in userdefined regions of the Cr film. We present x-ray microdiffraction microscopy results confirming the formation of a 90° spin-density wave propagation domain wall in Cr. This domain wall nucleates at the boundary defined by our Fe mask.Antiferromagnets play a critical and growing role in much of contemporary condensed matter physics and technology. Although traditionally used in magnetic storage devices (e.g., readheads in hard drives) for their supporting role as pinning layers, antiferromagnetic materials are now being used in emerging technologies as the principal layer governing transport properties of the device, such as spin valves utilizing antiferromagnetic tunneling anisotropic magnetoresistance [1]. With the emergence of these new technologies, the ability to understand

Antiferromagnetic domain wall as spin wave polarizer and retarder

“…[52,53] The domain wall structures have been observed in both types of antiferromagnetic materials [53][54][55], and can be effective controlled by using the exchange bias effects. [30,[56][57][58][59][60] Experimentally, it should be more straightforward to realize the spin wave polarizer and retarder proposed here using the synthetic antiferromagnetic wires used for the racetrack memory. [53] In conclusion, we demonstrated that the antiferromagnetic domain wall with Dzyaloshinskii-Moriya interaction naturally functions as a spin wave polarizer at low frequency, and a spin wave retarder (waveplate) at high frequency.…”

Intrinsic magnetization of antiferromagnetic textures

“…Pinning sites for domain walls can arise from impurities or crystal defects in the underlying lattice of AFMs. Although several studies have found that pinning effects in AFMs are small, [57][58][59] dislocations and impurities diffuse the effects on a single spin. In quasi-one-dimensional spin chains the introduction of a single impurity atom can be enough to destroy long-ranged antiferromagnetic order and domain wall configurations.…”

Antiferromagnetic Domain Wall Motion Induced by Spin Waves

“…Antiferromagnetic domains [11] and several forms of domain wall (DW) structures in AFMs have been observed [12]. Furthermore, DWs in AFMs can also be induced, controlled and engineered by exchange bias pinning forces [3,13].Progress in the field of antiferromagnetic spintronics requires the development of novel methods for exciting AFMs at the nanoscale. Many AFMs are insulating and cannot be affected by currents in the bulk; however, other approaches can be employed to excite an AFM.…”