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Abstract 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.
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Programmable Self‐Regulation with Wrinkled Hydrogels and Plasmonic Nanoparticle Lattices
Abstract This paper describes a self‐regulating system that combines wrinkle‐patterned hydrogels with plasmonic nanoparticle (NP) lattices. In the feedback loop, the wrinkle patterns flatten in response to moisture, which then allows light to reach the NP lattice on the bottom layer. Upon light absorption, the NP lattice produces a photothermal effect that dries the hydrogel, and the system then returns to the initial wrinkled configuration. The timescale of this regulatory cycle can be programmed by tuning the degree of photothermal heating by NP size and substrate material. Time‐dependent finite element analysis reveals the thermal and mechanical mechanisms of wrinkle formation. This self‐regulating system couples morphological, optical, and thermo‐mechanical properties of different materials components and offers promising design principles for future smart systems.
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- Award ID(s):
- 1848613
- PAR ID:
- 10448023
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small
- Volume:
- 18
- Issue:
- 1
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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