On-Chip Ultralow-Threshold Tunable CdSSe Nanobelt Lasers Excited by the Emission of Linked ZnO Nanowire.

The integration of optical waveguide and on-chip nanolasers source has been one of the trends in photonic devices. For on-chip nanolasers, the integration of nanowires and high antidamage ability are imperative. Herein, we realized the on-chip ultralow-threshold and wavelength-tunable lasing from alloyed CdSSe nanobelt chip that is excited by the emission from linked ZnO nanowires. ZnO nanowire arrays are integrated into CdSSe nanobelt chips by the dry transfer method. A one-dimensional (1D) ZnO nanowire forms high-quality optical resonators and serves as an indirect pumping light to stimulate CdSSe nanobelt chips, and then wavelength-tunable lasing is generated with the ultralow threshold of 3.88 μW. The lasing mechanism is quite different than direct excitation by nanosecond laser pulse and indirect pumping by ZnO emission. The ZnO-CdSSe blocks provide a new solution to realize nanowire lasing from linked nanowires rather than direct laser pumping and thus avoid the light direct damage under general nanosecond laser excitation.