The quest for a wide and bright supercontinuum source has received
significant attention, addressing pivotal challenges in ultra-fast
spectroscopy, imaging, and frequency metrology. Among the diverse
optical nonlinear mechanisms steering supercontinuum generation,
dispersive waves emerge as crucial contributors, providing heightened
spectral intensity, wavelength tunability, and superior temporal
coherence. Nevertheless, their generation is tightly bound by
waveguide geometry, limiting both their numbers and the wavelengths at
which they manifest. In this paper, we demonstrate the controlled
generation of multiple dispersive waves in fundamental optical
transverse mode by leveraging quasi phase-matching in an integrated
silicon nitride (Si3N4) waveguide. This approach involves
modulating the group velocity dispersion through varying the width of
the Si3N4 waveguide crossing anomalous and
normal dispersion, which facilitates the creation of diverse
dispersive waves in fundamental transverse electromagnetic (TE)
polarization at multiple phase-matched wavelengths. A wide nonlinear
optical spectral broadening surpassing conventional approaches is
achieved with good temporal and spatial coherence. Remarkably, the
generation of the multiple dispersive waves and the supercontinuum is
achieved by a 190-fs pulse duration pump with peak power as low as
110 W (24 pJ). This work offers flexibility to
manipulate dispersive waves in an integrated platform beyond current
dispersion engineering. It represents a significant step forward in
developing an integrated broadband source with a user-defined spectral
shape, accomplished with minimal pump power requirements.