Nanochannels with a 18-nm feature size and ultrahigh aspect ratio on silica through surface assisting material ejection

Abstract

Nanochannel structures with a feature size deeply under the diffraction limit and a high aspect ratio hold huge biomedical significance, which is especially challenging to be realized on hard and brittle materials, such as silica, diamond, and sapphire. By simultaneously depositing the pulse energy on the surface and inside the sample, nanochannels with the smallest feature size of 18 nm (∼1∕30λ) and more than 200 aspect ratios are achieved inside silica, the mechanism of which can be concluded as the surface assisting material ejection effect. Both the experimental and theoretical results prove that the coaction of the superficial "hot domain" and internal hot domain dominates the generation of the nanochannels, which gives new insights into the laser-material interacting mechanisms and potentially promotes the corresponding application fields.

High-Channel Spectral-Temporal Active Recording (H-STAR) for Femtosecond Scenes Observation in a Single-Shot

“…In addition, we can design the new coded aperture to match the H-STAR acquisition method in the future so that the number of channels can be slightly reduced to improve the field of view (FOV) of the entire system. This work will play an important role in the understanding of ultrafast processes such as femtosecond laser–matter interaction, − ultrashort pulse light field measurement, and atomic time scale. H-STAR will be a highly robust and suitable ultrafast imaging technique for studying transient, nonrepetitive events.…”

Wireless, Smart Hemostasis Device with All‐Soft Sensing System for Quantitative and Real‐Time Pressure Evaluation

“…FsL has the capability of cold machining due to its ultra-short pulse and ultra-high peak power and has significant application value in the field of micromaching. [37][38][39][40][41][42][43][44] The advantages of the FsL fabrication for microstructures are analyzed in Note S3 (Supporting information). Figure 2a shows the fabrication process of the LM-based capacitive pressure sensor.…”

Single Shot Generation of High‐Aspect‐Ratio Nano‐Rods from Sapphire by Ultrafast First Order Bessel Beam

“…Similar high-pressure conditions were observed for zero-order Bessel beam, leading to the generation of nano-spheroid on YAG [43] and in nano-channel formation with the so-called surface assisted material ejection. [44] Depending on the laser-deposited energy, the material at the center of the tube core can be in different physical states. As highlighted before, the three regimes we have identified depend on the fluence at the exit surface.…”

“…Similar high‐pressure conditions were observed for zero‐order Bessel beam, leading to the generation of nano‐spheroid on YAG [ 43 ] and in nano‐channel formation with the so‐called surface assisted material ejection. [ 44 ]…”