Photothermal spectroscopy measures the absorption spectra of materials by recording the wavelength-dependent heat generated upon the absorption of light. A heat sink converts the absorbed heat into a measurable quantity, such as an electrical signal in the case of thermoelectric sensors. The sensitivity of the technique critically depends on the thermal capacitance of the sensor, as this determines

Now, Fanglin Bao and colleagues at Purdue University and Michigan State University in the USA, have demonstrated a thermal-based sensing approach whose night-time imaging quality (depicted in the image) is more akin to daytime RGB images than to conventional night vision (Nature 619, 743–748; 2023). In their work, titled ‘Heat-assisted detection and ranging’, or HADAR, the team exploited emissivity

Light sheet microscopy offers rapid 3D imaging of biological specimens while limiting photodamage. Nature Photonics spoke with Elizabeth Hillman of Columbia University about its capabilities, promising applications and present limitations.

The interaction of terahertz waves with novel materials is bringing rich physics and new opportunities for applications.

Mansoor Sheik-Bahae, an exceptionally inventive scientist who made important contributions to nonlinear optics, optical refrigeration and laser science, passed away in July 2023, aged 67. He will be cherished for his sharp intellect, good humour, warm heart and the scientific legacy he leaves.

The nHGLA was composed of an array of microring lasers (pictured) based on 200-nm-thick InGaAsP multiple quantum wells. The inner radius and the width of the microrings were 3 μm and 600 nm, respectively. To introduce asymmetric coupling between nearest-neighbour microring cavities, they were connected with spiral-shaped coupling arms.

Activity in using photonics for subsea wireless communications and power generation is starting to make waves.

The laser community returned to Prague to celebrate science and to be connected, in person, again, while high-power lasers were in the limelight.

Optics is now going beneath the waves to give remote-operated vehicles and divers fast optical wireless data links. Nature Photonics spoke with Boon Ooi from KAUST, a leading researcher into underwater photonics research.

The GaP nanobeam, integrated on a silicon-on-insulator optical circuit, is engineered with a carefully designed pattern of holes so that it acts as a one-dimensional photonic crystal cavity with strong optomechanical coupling and good confinement of both optical modes and gigahertz mechanical modes. When light at a resonant wavelength of 1,550 nm is injected into the cavity, via an optical waveguide

Now, a fruitful collaboration between Stanford University, USA and Politecnico di Milano, Italy presents the feasibility of in situ training a PNN in the optical domain using a specially designed photonic integrated circuit (Science 380, 398–404; 2023). The researchers have experimentally demonstrated an optical physical implementation of the so-called backpropagation training algorithm, whose photonic

In order to simultaneously achieve this combination of mechanical robustness, optical transparency, and high conductivity, the Korean scientists found that a double network (DN) ionic hydrogel worked well as transparent and stretchable electrodes. The first and second networks were composed of chitosan crosslinked through the poly(ethylene glycol) crosslinker and poly(N-hydroxyethyl acrylamide-co-acrylamide)