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arXiv · 1201.4980

Near-field ablation threshold of cellular samples at mid-IR wavelengths

Deepa Raghu·Joan A. Hoffmann·Benjamin Gamari·M. E. Reeves
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Abstract

We report the near-field ablation of material from cellulose acetate coverslips in water and my- oblast cell samples in growth media, with a spot size as small as 1.5 {\mu}m under 3 {\mu}m wavelength radiation. The power dependence of the ablation process has been studied and comparisons have been made to models of photomechanical and plasma-induced ablation. The ablation mechanism is mainly dependent on the acoustic relaxation time and optical properties of the materials. We find that for all near-field experiments, the ablation thresholds are very high, pointing to plasma-induced ablation as the dominant mechanism.

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Deepa Raghu, Joan A. Hoffmann, Benjamin Gamari, M. E. Reeves. 2012-01-24. Near-field ablation threshold of cellular samples at mid-IR wavelengths. https://doi.org/10.1063/1.4719043

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