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We report in this letter the fabrication of edge-alignment-coupled whispering gallery mode photonic-molecule microdisk by femtosecond laser direct writing of dye-doped resins, which results in single-mode lasing output. Under picosecond laser pumping, the excited energy is distributed at the disk periphery and the coupling happens at the overlapping edge of two disks. As a result of mode coupling through Vernier effect, single-mode lasing is achieved in two-microdisk and three-microdisk coupled lasers of various sizes. The effect in the coupled system is confirmed by numerical simulation. This letter may open up a new avenue to the 3-D integrated optoelectronics. [ABSTRACT FROM PUBLISHER]

We experimentally demonstrate fabrication of a spiral-shaped polymer microdisk cavity by femtosecond laser direct writing via two-photon polymerization of dye-doped resins. This spiral microresonator supports highly directional emission from the notch with a high- Q factor exceeding 1.6\,\times \,10^{3} and a low lasing threshold at room temperature. Our numerical simulation results reveal that clockwise propagating high- Q$ whispering gallery-like modes may couple to the counterclockwise modes and give the directional output. Benefiting from the low cost and good chemical compatibility of polymer materials, the fabrication of such spiral-shaped polymer microlasers with high- $Q$ and unidirectional emission holds great potentials for use as elements of integrated organic optoelectronic devices. [ABSTRACT FROM PUBLISHER]

A novel solvent responsive polymer micromachine has been successfully fabricated by two-photon photopolymerization (TPP) of methacrylate-based photoresists. The moving part of the micromachine could be easily driven by interfacial solvent polarity induced swelling and shrinking of the photopolymer networks. Furthermore, the driving performance of the micromachine could be precisely modulated by varying the laser scanning step length during fabrication. [ABSTRACT FROM AUTHOR]

For the first time, proteins, a promising biocompatible and functionality-designable biomacromolecule material, acted as the host material to construct three-dimensional (3D) whispering-gallery-mode (WGM) microlasers by multiphoton femtosecond laser direct writing (FsLDW). Protein/Rhodamine B (RhB) composite biopolymer was used as optical gain medium innovatively. By adopting high-viscosity aqueous protein ink and optimized scanning mode, protein-based WGM microlasers were customized with exquisite true 3D geometry and smooth morphology. Comparable to previously reported artificial polymers, protein-based WGM microlasers here were endowed with valuable performances including steady operation in air and even in aqueous environments, and a higher quality value (Q) of several thousands (without annealing). Due to the 'smart' feature of protein hydrogel, lasing spectrum was responsively adjusted by step of ~0.4 nm blueshift per 0.83-mmol/L Na2SO4 concentration change (0 ~ 5-mmol/L in total leading to ~2.59-nm blueshift). Importantly, other performances including Q, FWHM, FSR, peak intensities, exhibited good stability during adjustments. So, these protein-based 3D WGM microlasers might have potential in applications like optical biosensing and tunable 'smart' biolasers, useful in novel photonic biosystems and bioengineering. [ABSTRACT FROM AUTHOR]