posted on 2021-05-24, 13:05authored byNegar Gheshlaghi, Sina Foroutan-Barenji, Onur Erdem, Yemliha Altintas, Farzan Shabani, Muhammad Hamza Humayun, Hilmi Volkan Demir
Here,
the first account of self-resonant fully colloidal μ-lasers
made from colloidal quantum well (CQW) solution is reported. A deep
patterning technique is developed to fabricate well-defined high aspect-ratio
on-chip CQW resonators made of grating waveguides and in-plane reflectors.
The fabricated waveguide-coupled laser, enabling tight optical confinement,
assures in-plane lasing. CQWs of the patterned layers are closed-packed
with sharp edges and residual-free lifted-off surfaces. Additionally,
the method is successfully applied to various nanoparticles including
colloidal quantum dots and metal nanoparticles. It is observed that
the patterning process does not affect the nanocrystals (NCs) immobilized
in the attained patterns and the different physical and chemical properties
of the NCs remain pristine. Thanks to the deep patterning capability
of the proposed method, patterns of NCs with subwavelength lateral
feature sizes and micron-scale heights can possibly be fabricated
in high aspect ratios.