This Special Topic Issue on Nonlinear Optics in 2D Materials contains an invited Perspective,1 an invited Tutorial,2 five invited articles,3–7 and two contributed articles8,9 that capture the most recent advances in the field. Guest Editors Nathalie Vermeulen and Stefano Palomba collaborated with APL Photonics Associate Editors Christelle Monat and Baohua Jia to organize the collection. The Guest Editors describe the special topic below:
“Atomically thin crystals forming a 2D sheet exhibit astonishing physical, chemical, and optical properties. The emergence of these materials, such as graphene, transition metal dichalcogenides, and others, has sparked widespread interest in the photonics community. Besides featuring an unprecedented performance for linear light-matter interactions, these materials also exhibit extraordinary nonlinear optical properties. One of the earliest demonstrated examples hereof is the ultrafast and broadband saturable absorption response of graphene in mode-locked lasers. Today, the range of nonlinear phenomena being explored in 2D materials also includes nonlinear THz interactions and plasmonics, wave mixing processes, self-focusing effects, and several others. Furthermore, the combination of 2D crystals with photonic/plasmonic integrated circuits and nanostructures, providing both tight light confinement/enhancement and the possibility of modulating the materials’ properties through electrical doping, has shown great promise for on-chip nonlinear photonic functionalities.
Notwithstanding the important progress researchers have made in recent years, there still is much to be discovered and explored in the domain of 2D-material-based nonlinear optics. A better understanding of both the fundamental physics and the practical implementation of nonlinear optical phenomena in 2D crystals would allow fully exploiting the great potential of this field. Hence, the aim of this special topic section is to focus on cutting-edge research that provides new insights into the nonlinear optical properties of 2D materials and strongly advance the knowledge and expertise in this exciting research branch.”
We hope that you find this snapshot of the field to be both useful and enjoyable.
