Wavefront Microscopy Using Quadriwave Lateral Shearing Interferometry: From Bioimaging to Nanophotonics

Abstract

Common cameras are only sensitive to the intensity of light, discarding an essential feature of a light wave: its phase profile or, equivalently, its wavefront profile. This Review focuses on a rising wavefront imaging technique called quadriwave lateral shearing interferometry (QLSI), based on the simple use of a 2dimensional diffraction grating, aka a cross-grating, in front of a regular camera. We detail the working principle of QLSI and its implementation on an optical microscope. We highlight its microscopy applications in bioimaging and nanophotonics, in particular for the characterization of living cells, nanoparticles, 2D materials, metasurfaces, microscale temperature gradients, and surface topography. Finally, we draw a critical comparison of QLSI with current quantitative phase microscopy techniques, namely, digital holography microscopy (DHM), spatial light interference microscopy (SLIM), and diffraction phase microscopy (DPM).

Thermometries for Single Nanoparticles Heated with Light

“…(f) Scheme of the wavefront distortion. Adapted with permission from ref . Copyright 2023 American Chemical Society.…”

Anti Stokes Thermometry of Plasmonic Nanoparticle Arrays

“…However, these techniques require previous calibrations of the probes and yield a temperature that is not necessarily the same as the NP. In addition, wavefront microscopy [30][31][32] can be used to map temperature distributions around heated NPs immersed in a liquid, with diffraction-limited resolution, by probing the wavefront distortion created by the temperature-induced variation of the refractive index of the liquid. [32] More recently, an emerging method called Anti Stokes (AS) thermometry offers promising solutions for measuring the temperature of plasmonic NPs themselves.…”

“…In addition, wavefront microscopy [30][31][32] can be used to map temperature distributions around heated NPs immersed in a liquid, with diffraction-limited resolution, by probing the wavefront distortion created by the temperature-induced variation of the refractive index of the liquid. [32] More recently, an emerging method called Anti Stokes (AS) thermometry offers promising solutions for measuring the temperature of plasmonic NPs themselves. The method capitalizes on the temperature-dependent behavior of the AS photoluminescence (PL) emission spectrum of the plasmonic material when illuminated by a continuous-wave laser.…”

“…In addition, wavefront microscopy [ 30–32 ] can be used to map temperature distributions around heated NPs immersed in a liquid, with diffraction‐limited resolution, by probing the wavefront distortion created by the temperature‐induced variation of the refractive index of the liquid. [ 32 ]…”

Quantitative Microscale Thermometry in Droplets Loaded with Gold Nanoparticles

“…Cross-grating wavefront microscopy (CGM) − is a technique based on quadriwave lateral shearing interferometry that has several advantages: it is simple, compact, and poorly sensitive to environmental perturbations. It also benefits from high signal/noise ratio and high spatiotemporal resolution .…”