Magnetic Field Tunable Polaritons in the Ultrastrong Coupling Regime in CrSBr.

Collective excitations of bound electron-hole pairs, i.e., excitons, are ubiquitous in condensed matter systems, and it has been shown that they can strongly couple to other degrees of freedom, such as spin, orbital, and lattice.

Transferable Optical Enhancement Nanostructures by Gapless Stencil Lithography.

Optical spectroscopy techniques are central for the characterization of two-dimensional (2D) quantum materials. However, the reduced volume of atomically thin samples often results in a cross section that is far too low for conventional optical methods to produce measurable signals. In this work, we developed a scheme based on the stencil lithography technique to fabricate transferable optical enhancement nanostructures for Raman and photoluminescence spectroscopy.

Shape and deposition angle control of silver film-over-nanosphere SERS substrates.

Thin metallic films on dielectric nanospheres are demonstrated to have a high potential for the fabrication of cost-effective SERS substrates. In addition to the morphological advantages that nanospheres offer for attaining a high density of hot spots, possessing shape adjustability by uncomplicated thermal treatment makes them an attractive platform for tuneable SERS substrates. Furthermore, when combined with the oblique angle metal deposition technique, adjustable gaps at a high density and adjustable shape of metal films, such as Ag films, can be achieved on nanospheres.