Abstract
We present a detailed analysis of the in-plane magnetic vector configuration in head-to-head/tail-to-tail stripe domain patterns of nominal 5 μm width. The patterns have been created by He-ion bombardment induced magnetic patterning of a CoFe/IrMn3 exchange bias thin-film system. Quantitative information about the chemical and magnetic structure is obtained from polarized neutron reflectometry (PNR) and off-specular scattering (OSS). The technique provides information on the magnetic vector orientation and magnitude along the lateral coordinate of the sample, as well as the chemical and magnetic layer structure as a function of depth. Additional sensitivity to magnetic features is obtained through a neutron wave field resonance, which is fully accounted for in the presented analysis. The scattering reveals a domain width imbalance of 5.3 to 3.7 μm of virgin and bombarded stripes, respectively. Further, we report that the magnetization in the bombarded stripe significantly deviates from the head-to-head arrangement. A domain wall of 0.6 μm with homogeneous magnetization direction is found to separate the two neighboring domains. The results contain detailed information on length scales and magnetization vectors provided by PNR and OSS in absolute units. We illustrate the complementarity of the technique to microscopy techniques for obtaining a quantitative description of imprinted magnetic domain patterns and illustrate its applicability to different sample systems.
Highlights
Magnetic materials with engineered magnetic textures on micrometer length scales [1,2,3] have attracted attention due to their possible application in lab-on-a-chip devices [4,5,6,7], controlled self-organization [8,9], magnonics [10], controllable optically active surfaces [11] and biosensor applications [12]
We present a detailed analysis of the in-plane magnetic vector configuration in head-to-head/tail-to-tail stripe domain patterns of nominal 5 μm width
The magnetic contrast in such measurements is determined by the orientation of the surface wave vector projection k|| to the magnetization, where a maximum contrast is achieved for parallel to antiparallel alignment [24,41]
Summary
Magnetic materials with engineered magnetic textures on micrometer length scales [1,2,3] have attracted attention due to their possible application in lab-on-a-chip devices [4,5,6,7], controlled self-organization [8,9], magnonics [10], controllable optically active surfaces [11] and biosensor applications [12]. The technique is based on magnetic textures engineered by light-ion irradiation of thin-film exchange bias systems in oriented applied magnetic fields. The effect is observed as a shift of the hysteresis loop along the applied field axis after setting the AF. This setting takes place by cooling the AF through its blocking temperature in an applied field strong enough to saturate the ferromagnet. In the case of light-ion bombardment, changes in the exchange bias direction and magnitude have been explained by hyper-thermal effects and microscopic changes in the defect density at the interface between the FM and AF and deeper in the AF [20,21,22]. For IBMP, a protective photoresist mask forming the pattern is applied prior to the bombardment, which generates the magnetic texture. The bombardment process may lead to irreversible structural and magnetic changes, such as swelling and decay in exchange bias or magnetization of the FM [20,23], which can lead to instabilities in the magnetic potential landscape
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
