High-Order-Mode supercontinuum generation based on shortcut to adiabaticity coupling.

• Using a Shortcut to Adiabatic (STA) approach to achieve specific high order modes coupling in the waveguide and generate SCG. • Compared to conventional angle tilting edge coupling (<7%) for high order mode, the coupling efficiency over 80 % for specific high order mode from fundamental mode in the broadband spectrum was recorded and demonstrated, confirming the functionality of mode coupling. The observed octave spanning SCG (at level of 30 dB span nearly 600 nm) from TE 10 mode was characterized. • The fabrication tolerance r for waveguide width variations of ± 13 nm is constant with only slight changes (less than 10 %). • This is first time, to our best knowledge, the efficient octave spanning SCG can be generated from specific high order within nonlinear waveguide. Broadband optical sources have been attracting widespread attention because of their remarkable potential for application to quantum technology. One of the major obstacles to realization of such applications is the weak anomalous group velocity dispersion (GVD) of these sources and low coupling efficiency of high order mode for generating supercontinuum generation (SCG). In this work, using a shortcut to adiabaticity (STA) approach, high order modes can be excited selectively with coupling efficiency of more than 80 % to enable octave spanning supercontinuum generation within a waveguide composed of tantalum pentoxide (Ta 2 O 5), which is a high nonlinear refractive index material. The SCG over the range from 650 nm to 1300 nm, which corresponds to one octave, was demonstrated and analyzed when the material was pumped using a femtosecond laser with a center wavelength of 1030 nm. [ABSTRACT FROM AUTHOR]