Second-harmonic generation (SHG) in a near-field optical-fiber probe was observed. The tip of the probe consists of a triple-tapered fiber with an aluminum coating. For a fiber probe with an aperture size of 100 nm, the SHG conversion factor was 2.0 × 10<sup>-11</sup>cm<sup>2</sup>/W , which is as large as that of a 5-mm KDP crystal. In a probe-to-probe experiment, we demonstrated that SHG took place at the aluminum coating on the fiber probe.
© 2001 Optical Society of America
Tadashi Kawazoe, Takashi Shimizu, and Motoichi Ohtsu, "Second-harmonic generation in a near-field optical-fiber probe," Opt. Lett. 26, 1687-1689 (2001)