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arXiv · 2112.03671

Nanometers-thick Ferromagnetic Surface Produced by Laser Cutting of Diamond

Annette Setzer·Pablo D. Esquinazi·Sergei Buga·Milena T. Georgieva·Tilo Reinert·Tom Venus·Irina Estrela-Lopis·Andrei Ivashenko·Maria Bondarenko·Winfried Böhlmann·Jan Meijer
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Abstract

In this work, we demonstrate that cutting diamond crystals with a laser (532~nm wavelength, 0.5~mJ energy, 200~ns pulse duration at 15~kHz) produces a $\lesssim 20~$nm thick surface layer with magnetic order at room temperature. We have measured the magnetic moment of five natural and six CVD diamond crystals of different size, nitrogen content and surface orientations with a SQUID magnetometer. A robust ferromagnetic response at 300~K is observed only for crystals that were cut with the laser along the (100) surface orientation. The magnetic signals are much weaker for the (110) and negligible for the (111) orientations. We attribute the magnetic order to the disordered graphite layer produced by the laser at the diamond surface. The ferromagnetic signal vanished after chemical etching or after moderate temperature annealing. The obtained results indicate that laser treatment of diamond may pave the way to create ferromagnetic spots at its surface.

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Annette Setzer, Pablo D. Esquinazi, Sergei Buga, Milena T. Georgieva, Tilo Reinert, Tom Venus, Irina Estrela-Lopis, Andrei Ivashenko, Maria Bondarenko, Winfried Böhlmann, Jan Meijer. 2021-12-07. Nanometers-thick Ferromagnetic Surface Produced by Laser Cutting of Diamond. https://doi.org/10.3390/ma15031014

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