Fig. 1.

(A) Schematic illustration of the apparatus for producing and monitoring single vapor nanobubbles. A near-infrared laser is focused onto a gold-film–coated glass coverslip to induce local boiling of water, resulting in nanosized vapor bubbles. (B) The increased local temperature reduces the refractive index of surrounding medium before the formation of vapor nanobubbles, accompanying with a dark shadow in SPRM image (thermal effect). Sudden nucleation of single nanobubble disturbed SPPs, resulting in a wave-like pattern (bubble). (C) SPRM intensity curve and (D) the corresponding time-lapsed SPRM images of a representative nanobubble event, consisting of the prenucleation, formation, growth, and disappearance stages (Scale bar: 5 μm).