Micromagnetic Simulations of Concentration Detection Capability of Large-Area and Low-Aspect-Ratio GMR Sensors in Biomedical Diagnostics

Since the discovery of Giant Magnetoresistance(GMR) , it has found many applications in sensors. One of these key areas is for biomedical sensing. GMR biosensors with large-area and low-aspect-ratio were demonstrated experimentally with ultra high sensitivity, followed by a relatively simplified theoretical explanation. This study presents a systematic micromagnetic simulation analysis of large-area and low-aspect-ratio GMR sensors, with a particular focus on two key regimes: the linear portion before saturation by the magnetic nanoparticle(MNP) interaction with the sensor and the flattening out due to sensor saturation. This study presents a simulation-based analysis of large-area and low-aspect-ratio GMR sensors using micromagnetic simulations for biomedical diagnostic applications. We investigate various MNP types and sizes. Through systematic simulations, we compare sensitivity to concentration and highlight the influence of MNP characteristics and concentration on the large-area GMR sensor's performance. This study not only furthers the understanding of large-area and low-aspect-ratio GMR sensor behavior, but also paves the way for future targeted experimental research and development in this promising field.

自巨型磁阻（Giant Magnetoresistance，GMR）的发现以来，其在传感器领域的应用日益广泛。其中，生物医学传感领域便是其关键应用领域之一。实验上已成功展示了大面积、低宽高比的 GMR 生物传感器，其具有超高的灵敏度，并伴随着相对简化的理论解释。本研究对大面积、低宽高比的 GMR 传感器进行了系统性的微观磁模拟分析，特别关注两个关键阶段：由磁性纳米颗粒（Magnetic Nanoparticle，MNP）与传感器的相互作用导致的饱和前的线性部分以及由于传感器饱和而引起的平坦化。本研究利用微观磁模拟对大面积、低宽高比的 GMR 传感器进行了基于模拟的分析，旨在生物医学诊断应用中。我们探讨了不同类型和大小的 MNP，并通过系统性的模拟，对比了其对浓度的敏感性，并突出了 MNP 特征和浓度对大面积 GMR 传感器性能的影响。本研究不仅深化了对大面积、低宽高比 GMR 传感器行为机制的理解，而且为该领域具有广阔前景的实验研究与发展指明了道路。