Nanoscale Mechanical Manipulation of Ultrathin SiN Membranes Enabling Infrared Near-Field Microscopy of Liquid-Immersed samples.

Scattering scanning near-field optical microscopy (s-SNOM) is a powerful technique for mid-infrared spectroscopy at nanometer length scales. By investigating objects in aqueous environments through ultrathin membranes, s-SNOM has recently been extended toward label-free nanoscopy of the dynamics of living cells and nanoparticles, assessing both the optical and the mechanical interactions between the tip, the membrane and the liquid suspension underneath. Here, the study reports that the tapping AFM tip induces a reversible nanometric deformation of the membrane manifested as either an indentation or protrusion.

Revealing Mode Formation in Quasi-Bound States in the Continuum Metasurfaces via Near-Field Optical Microscopy.

Photonic metasurfaces offer exceptional control over light at the nanoscale, facilitating applications spanning from biosensing, and nonlinear optics to photocatalysis. Many metasurfaces, especially resonant ones, rely on periodicity for the collective mode to form, which makes them subject to the influences of finite size effects, defects, and edge effects, which have considerable negative impact at the application level. These aspects are especially important for quasi-bound state in the continuum (BIC) metasurfaces, for which the collective mode is highly sensitive to perturbations due to high-quality factors and strong near-field enhancement.

Probing the micro- and nanoscopic properties of dental materials using infrared spectroscopy: A proof-of-principle study.

The preservation of oral health over a person's lifespan is a key factor for a high quality of life. Sustaining oral health requires high-end dental materials with a plethora of attributes such as durability, non-toxicity and ease of application. The combination of different requirements leads to increasing miniaturization and complexity of the material components such as the composite and adhesives, which makes the precise characterization of the material blend challenging.

Sewage Sludge Management at District Level: Reduction and Nutrients Recovery via Hydrothermal Carbonization.

In this study, two scenarios of a municipal wastewater treatment plant (WWTP) are presented, which include the integration of the hydrothermal carbonization (HTC) process into the sludge line as a post-treatment of the anaerobic digestion (AD) process. The objective of the simulation is to investigate the performances of AD + HTC treatment to reduce sludge production and improve nutrient and energy recovery. For this purpose, the scheme of an under-construction WWTP was considered, named Trento 3 (Trento, Italy) and with a treatment capacity of 300,000 PE.

Infrared-spectroscopic, dynamic near-field microscopy of living cells and nanoparticles in water.

Infrared fingerprint spectra can reveal the chemical nature of materials down to 20-nm detail, far below the diffraction limit, when probed by scattering-type scanning near-field optical microscopy (s-SNOM). But this was impossible with living cells or aqueous processes as in corrosion, due to water-related absorption and tip contamination. Here, we demonstrate infrared s-SNOM of water-suspended objects by probing them through a 10-nm thick SiN membrane.