A plasmonic nanolaser architecture that can produce white‐light emission is reported. A laser device is designed based on a mixed dye solution used as gain material sandwiched between two aluminum nanoparticle (NP) square lattices of different periodicities. The (±1, 0) and (±1, ±1) band‐edge surface lattice resonance (SLR) modes of one NP lattice and the (±1, 0) band‐edge mode of the other NP lattice function as nanocavity modes for red, blue, and green lasing respectively. From a single aluminum NP lattice, simultaneous red and blue lasing is realized from a binary dye solution, and the relative intensities of the two colors are controlled by the volume ratio of the dyes. Also, a laser device is constructed by sandwiching dye solutions between two Al NP lattices with different periodicities, which enables red–green and blue–green lasing. With a combination of three dyes as liquid gain, red, green, and blue lasing for a white‐light emission profile is realized.
A sustainable, lithography‐free process is demonstrated for generating non fading plasmonic colors with a prototype device that produces a wide range of vivid colors in red, green, and blue (RGB) ([0‐1], [0‐1], [0‐1]) color space from violet (0.7, 0.72, 1) to blue (0.31, 0.80, 1) and from green (0.84, 1, 0.58) to orange (1, 0.58, 0.46). The proposed color‐printing device architecture integrates a semi‐transparent random metal film (RMF) with a metal back mirror to create a lossy asymmetric Fabry‐Pérot resonator. This device geometry allows for advanced control of the observed color through the five‐degree multiplexing (Red‐Green‐Blue (RGB) color space, angle, and polarization sensitivity). An extended color palette is then obtained through photomodification process and localized heating of the RMF layer under various femtosecond laser illumination conditions at the wavelengths of 400 nm and 800 nm. Colorful design samples with total areas up to 10 mm2and 100 µm resolution are printed on 300‐nm‐thick films to demonstrate macroscopic personalized high‐resolution color generation. The proposed printing approach can be extended to other applications including laser marking, anti‐counterfeiting, and chromo‐encryption.
more » « less- PAR ID:
- 10474185
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Optical Materials
- Volume:
- 12
- Issue:
- 4
- ISSN:
- 2195-1071
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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