Shape-Engineering of Self-Assembled Organic Single Microcrystal as Optical Microresonator for laser Applications

Abstract

Single micro/nanocrystals based on π-conjugated organic molecules have caused tremendous interests in the optoelectronic applications in laser, optical waveguide, nonlinear optics, and field effect transistors. However, the controlled synthesis of these organic micro/nanocrystals with regular shapes is very difficult to achieve, because the weak interaction (van der Waals' force, ca. 5 kJ/mol) between organic molecules could not dominate the kinetic process of crystal growth. Herein, we develop an elaborate strategy, selective adhesion to organic crystal plane by the hydrogen-bonding interaction (ca. 40 kJ/mol), for modulating the kinetic process of the formation of microcrystal, which leads to the self-assembly of one organic molecule 3-[4-(dimethylamino)phenyl]-1-(2-hy-droxyphenyl)prop-2-en-1-on (HDMAC) into one-dimensional (1D) microwires and 2D microdisks respectively. Furthermore, these as-prepared microcrystals demonstrate shape-dependent microresonator properties that 1D microwires act as Fabry-Pérot (FP) mode lasing resonator and 2D microdisks provide the whispering-gallery-mode (WGM) resonator for lasing oscillator. More significantly, through the investigation of the size-effect on the laser performance, single-mode lasing at red wavelength was successfully achieved in the self-assembled 2D organic microdisk at room temperature. These easily fabricated organic single-crystalline microcrystals with controlled shapes are the natural laser sources, which offer considerable promise for the multi-functionalities of coherent light devices integrated on the optics microchip.

Near-Infrared Lasing from Small-Molecule Organic Hemispheres

“…47 The mode spacing Δλ m between two adjacent peaks around 720 nm is 26.3 and 10.2 nm for these two corresponding hemispheres with diameters of 3.3, and 8.5 μm, respectively (Figure 5a). The increasing number of modes with the increasing size of hemispheres indicates that the optical modulation is certainly based on the confinement of photons within the hemispherical optical resonator.…”

Photonic Microrods Composed of Photoswitchable Molecules: Erasable Heterostructure Waveguides for Tunable Optical Modulation

“…Nano-and microscale organic solids [1][2][3][4] are emerging as promising photonic materials to realize miniaturized device applications such as wave guides, [3][4][5][6][7][8][9][10][11] lasers, [ 12,13 ] resonators, [ 14,15 ] circuits, [ 16 ] and optical fi lters. [ 17 ] In the next level of complexity, responsive organic solids which can change their shape and dimensions with respect to external perturbation are known to exhibit switchable photonic properties.…”

Self‐Assembly of a β‐Peptide Foldamer: The Role of the Surfactant in Three‐Dimensional Shape Selection

“…We anticipate that this systematic study of foldectures using a well‐defined model system provides in‐depth understanding of how ionic surfactants recognize functional anisotropy and control shape evolution during the self‐assembly of organic materials. We sincerely believe this study will provide fruitful insight that can be applied to the efficient use of surfactants in the synthesis of crystalline organic nanomaterials with optoelectronic properties ,…”