Functional Optical Metalens Made From 2D Materials

New types of ultrathin materials that could replace the conventional glass lenses used in cameras and imaging systems. Typically the new sorts of metalenses are not made of glass. Instead, they consist of materials constructed at the nanoscale in arrays of columns or fin-like structures like Fresnel lenses.

But although metalenses are much thinner than glass lenses, they still rely on relatively high aspect ratio structures, in which the column or fin-like structures are much taller than they are wide, making them prone to collapsing and falling over. Furthermore, these structures have always been near the wavelength of light they’re interacting with in thickness — until now.

A team from the University of Washington, MD, USA, (UW) and National Tsing Hua University, Taiwan, have developed functional metalenses that measure between one-tenth to one-half the thickness of the wavelengths of light that they focus. The metalenses, constructed from layered 2D materials, are as thin as 190 nm across. The work has been described in Nano Letters.

Read more