Nonlinear optics articles from across Nature Portfolio

Imaging in the water window has traditionally relied on large synchrotron radiation sources. Now, a tabletop tunable X-ray source which generates water-window X-ray photons from a low energy electron beam interacting with a van der Waals crystal has been demonstrated.

A nonlinear optical response to a new form of light, dubbed chiral topological light owing to its local chirality and global topological characteristics, is enabling unprecedented enantiosensitivity and robustness of chiro-optical spectroscopies as a result of structured light–matter interactions at deep subwavelength scales.

Here, the authors develop a concept for the synthesis of multiple narrow and intense optical spectral lines over a broad infrared region. This concept constitutes a promising way for multi-gas detection and multispectral microscopic imaging.

Tabletop, water-window X-rays are generated using free-electron-driven van der Waals materials. The X-ray energy from the source can be tuned across the water window, and the established fundamental scaling laws for the tunable photon flux may enable the design of powerful emitters based on free-electron-driven quantum materials.

Imaging in the water window has traditionally relied on large synchrotron radiation sources. Now, a tabletop tunable X-ray source which generates water-window X-ray photons from a low energy electron beam interacting with a van der Waals crystal has been demonstrated.

A nonlinear optical response to a new form of light, dubbed chiral topological light owing to its local chirality and global topological characteristics, is enabling unprecedented enantiosensitivity and robustness of chiro-optical spectroscopies as a result of structured light–matter interactions at deep subwavelength scales.

Parity-Time symmetric micro-resonators utilizing nonlinear four-wave mixing, now surpass the bandwidth-efficiency limit for optical signal processing, achieving a remarkable 100-fold efficiency boost.

The nonlinear optical response of achiral molecules spread on chiral nanostructured substrates and subjected to circularly polarized light is examined. The experiment is a step towards confirming a long-standing theoretical prediction: hyper-Raman optical activity.

Inspired by non-trivial band topology and the variety of correlated electronic phases in moiré superlattices formed in van der Waals materials, scientists are finding alternative material platforms to exploit the rich phenomena arising from the twist-angle degree of freedom.