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Techniques for imaging and characterizing magnetic samples have been widely used in many areas of research involving
magnetic materials. Nowadays, magnetic microscopy techniques play a critical role in characterizing magnetic thin film
structures. In considering the various techniques, optical techniques offer some unique advantages over alternative techniques
(e.g. MFM), as they are least affected by magnetic noise and, for the same underlying reasons, have also proven to be more
suitable for "high speed" magnetization measurements of magnetization dynamics, which are increasingly important in many of
today's research scopes.
At the same time, development of metamaterials are opening the doors for newly behaving materials, such as those
demonstrating negative refractive index, potentially useful in a variety of applications, such as imaging. Metamaterials
deploying arrays of silicon particles, and even alternating silicon particles and split ring resonators have recently been shown to
demonstrate interesting behavior, such as negative magnetic susceptibility and large resonant peaks in the Terahertz regime.
Such high frequencies offer the potential bandwidth of extraordinarily fast dynamics, which are increasingly being generated in
magnetic materials, for example, in optically-induced demagnetization and all-optical magnetic recording.
Here, initial investigations toward ultra high-speed imaging and/or information extraction from magnetic samples is discussed
considering metamaterials deploying mainly spherical particle arrays. In addition to the frequency spectrums of the system, the
response of the system to external magnetic fields and background permeability changes due to external fields are investigated.
Our results suggest a significant potential of metamaterials for use in probing information from magnetic materials.
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