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

TL;DR

This study investigates near-field ablation of biological samples using mid-IR wavelengths, revealing plasma-induced ablation as the primary mechanism with high ablation thresholds.

Contribution

It provides experimental data on near-field ablation thresholds at mid-IR wavelengths for biological samples and compares the results to theoretical models.

Findings

Ablation thresholds are very high across experiments.

Ablation mechanism is mainly plasma-induced.

Ablation spot size as small as 1.5 μm.

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.