Next-generation on-chip modelocked lasers based on novel material combinations and enhanced (non-)linear optical responses (LASMORE)

Modelocked pulsed lasers have a widespread impact on modern science and society, and can
nowadays be integrated on tiny chips based on ‘active’ semiconductor material platforms such as the
indium phosphide (InP) platform. On-chip modelocked InP lasers typically consist of an InP
waveguide resonator containing an InP amplifier and a nonlinear-optical InP saturable absorber (SA).
Notwithstanding the major progress made in their development, it remains challenging for these onchip lasers to generate both a high peak output power (>1W) and a short pulse duration (<1ps), as
crucially required for applications in e.g. LIDAR, bio-imaging and micro-machining. To enable both
short pulses and high powers, we propose combining on-chip modelocked InP lasers with (a) twodimensional materials such as graphene and MoS2 for realizing new nonlinear-optical SAs with an
ultrafast response time, and with (b) ‘passive’ chip material platforms such as the silicon nitride (SiN)
platform to optimize the linear-optical properties of the laser resonator and particularly its dispersion.
This approach promises pulse durations below 330fs and peak output powers above 1W. The
envisaged research will create groundbreaking new insights into the (non-)linear optical physics of
the combined materials and the resulting (non-)linear optical response enhancement. It will also
yield next-generation on-chip modelocked laser devices serving as new building blocks for photonic
chips with very wide applicability.