Physics

Laser linewidth

Infrared

Optomechanics

Laser

Nonlinear optics

Resonator

Continuous wave

Terahertz radiation

Plasmon

Optics

Photon upconversion

Materials science

Photonics

Raman spectroscopy

Optoelectronics

Science

Optomechanical upconversion Molecules have rich signatures in their spectra at infrared wavelengths and are typically accessed with dedicated spectroscopic instrumentation. Chen et al . and Xomalis et al . report optomechanical frequency upconversion from the mid-infrared to the visible domain using molecular vibrations coupled to a plasmonic nanocavity at ambient conditions (see the Perspective by Gordon). Using different nanoantenna designs, one with a nanoparticle-on-resonator and the other with nanoparticle-in-groove, both approaches show the ability to upconvert the mid-infrared vibrations of the molecules in the nanocavity to visible light wavelengths. The effect could be used to simplify infrared spectroscopy, possibly with single-molecule sensitivity. —ISO

Continuous-wave frequency upconversion with a molecular optomechanical nanocavity