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arXiv · 0908.3038

Entrapment of magnetic micro-crystals for on-chip electron spin resonance studies

N. Groll·S. Bertaina·M. Pati·N. S. Dalal·I. Chiorescu
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Abstract

On-chip Electron Spin Resonance (ESR) of magnetic molecules requires the ability to precisely position nanosized samples in antinodes of the electro-magnetic field for maximal magnetic interaction. A method is developed to entrap micro-crystals containing spins in a well defined location on a substrate's surface. Traditional cavity ESR measurements are then performed on a mesoscopic crystal at 34 GHz. Polycrystalline diluted Cr$^{5+}$ spins were entrapped as well and measured while approaching the lower limit of the ESR sensitivity. This method suggests the feasibility of on-chip ESR measurements at dilution refrigerator temperatures by enabling the positioning of samples atop an on-chip superconducting cavity.

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N. Groll, S. Bertaina, M. Pati, N. S. Dalal, I. Chiorescu. 2009-08-21. Entrapment of magnetic micro-crystals for on-chip electron spin resonance studies. https://doi.org/10.1063/1.3207774

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