Observation of Lasing Emission from Carbon Nanodots in Organic Solvents

Abstract

Lasing is observed from carbon nanodots (C-dots) dispersed into a layer of poly(ethylene glycol) coated on the surface of optical fibers under 266 nm optical excitation. This is due to the enhancement of photoluminescence intensity via the esterification of carboxylic groups of the C-dots, and the formation of high-Q cylindrical microcavities to support second-type whispering gallery modes.

Blue Liquid Lasers from Solution of CdZnS/ZnS Ternary Alloy Quantum Dots with Quasi‐Continuous Pumping

“…According to the 2D WGM model, the FSR is given by [ 31 ] : / 2 FSR nD λ π = , which means that FSR is theoretically inversely proportional to the inner fi ber diameter, further corroborating the WGM lasing mechanism. Thanks to the high refractive index contrast between the solution (1.56) and the glass (1.47 at 440 nm), [ 38 ] the QDs emission is strongly confi ned inside the cavity. This is supported by numerical simulation using fi nite element method (FEM) available from COMSOL multiphysics as shown in Figure 3 c. [ 31,35 ] The electric fi eld distribution in the radial direction of WGM ( p = 1, m = 600) in a 54 µm-diameter capillary tube exhibits effective optical confi nement close to the cavity boundary.…”

Electron–hole recombination dynamics in carbon nanodots

“…Currently, C-dots are readily produced on large scales by several tunable methods [4][5][6][7]. Therefore, C-dots offer great potential for a broad range of applications, including biological imaging [8,9], drug delivery [10], sensors [8], photovoltaics [11], light-emitting diodes [12][13][14], and lasers [15].…”

One-step, green, and economic synthesis of water-soluble photoluminescent carbon dots by hydrothermal treatment of wheat straw, and their bio-applications in labeling, imaging, and sensing

“…Importantly, the simple and inexpensive one-step synthesis [17][18][19] allows location on their surface, in addition to carboxylic groups (which is common), of the reactive amino groups, and this strongly facilitates their functionalization [20] , which further allows C-dots to find applications in biological imaging [21] , drug delivery [22] , sensing [23][24] , photovoltaic devices [25][26] , lasing [27] , or catalysis [16] . All of these have made C-dots become a "new star" member of carbon material family for all over the scientific researching fields and industries.…”