As disclosed herein, a plasmonic up-converter apparatus includes an
excitation source operable to emit electromagnetic radiation at an
excitation frequency and at least one array of nanofeatures. The at least
one array of nanofeatures is configured to produce an emission spectrum
responsive to irradiation by the electromagnetic radiation. The emission
spectrum has an intensity at a second harmonic frequency or a third
harmonic frequency approximately equal to an intensity at a fundamental
harmonic frequency, with the fundamental harmonic frequency being
approximately equal to the excitation frequency. Additional aspects are
directed to a display that utilizes any of the disclosed plasmonic
up-converter apparatuses, a laser in which a laser medium is optically
pumped using electromagnetic radiation produced by one of the disclosed
plasmonic up-converter apparatuses, and methods of up-converting
electromagnetic radiation.