Measurement of submicrometre diameters of tapered optical fibres using harmonic generation.
Applications of subwavelength-diameter optical fibres in nonlinear optics require precise knowledge of the submicrometre fibre waist diameter. We demonstrate a new technique for optical measurement of the diameter based on second- and third-harmonic generation with an accuracy of better than 2%. To generate the harmonic light, inter-modal phase matching must be achieved. We find that the phase-matching condition allows us to unambiguously deduce the fibre diameter from the wavelength of the harmonic light. High-resolution scanning electron microscope imaging is used to verify the results.
Wiedemann
Ulrich
U
Institut für Angewandte Physik, Universität Bonn, Wegelerstr. 8, 53115 Bonn, Germany. wiedemann@iap.uni-bonn.de
Karapetyan
Konstantin
K
Dan
Cristian
C
Pritzkau
Dimitri
D
Alt
Wolfgang
W
Irsen
Stephan
S
Meschede
Dieter
D