Dong Yoon Oh
A 40 cm-long silica spiral waveguide is fabricated on a 1 cm x 1 cm silicon chip using photolithography. The dispersion of the waveguide is optimized for supercontinuum generation, the nonlinear optical process in which an ultrashort pulse undergoes an extreme spectral broadening and results in a broadband frequency comb. In this case, initially invisible laser light becomes visible through supercontinuum generation. Diverse colors of light are observed in the waveguide by launching pulses with various energies. Photographs of the spiral are embedded in an artificial background. The work is done by Dong Yoon Oh, Ki Youl Yang and Kerry Vahala.