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Abstract 2D photonic crystal (PhC) lasing from an InP nanowire array still attached to the InP substrate is demonstrated for the first time. The undoped wurtzite InP nanowire array is grown by selective area epitaxy and coated with a 10 nm thick Al2O3film to suppress atmospheric oxidation and band‐bending effects. The PhC array displays optically pumped lasing at room temperature at a pulsed threshold fluence of 14 µJ cm−2. At liquid nitrogen temperature, the array shows lasing under continuous wave excitation at a threshold intensity of 500 W cm−2. The output power of the single mode laser line reaches values of 470 µW. Rate equation calculations indicate a quality factor ofQ ≈ 1000. Investigations near threshold reveal that lasing starts from isolated islands within the pumped region before coherently merging into a single homogeneous area with increasing excitation power. This field emits a lasing mode with an average off‐normal angle of ≈6°. Single mode lasing with the nanoarray still attached to the InP substrate opens new design opportunities for electrically pumped PhC laser light sources.
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A Conformational Study of the 10-23 DNAzyme via Programmed DNA Self-Assembly
This communication measures the inter-helical angle of the 10-23 DNAzyme-substrate complex by atomic force microscopy (AFM). specificity. Herein, we have devised a strategy to assemble the DNAzyme-substrate complex into a periodic DNA 2D array, which allows reliable study of the conformation of the 10-23 DNAzyme by AFM imaging and fast Fourier transform (FFT). Specifically, the angle between the two flanking helical domains of the catalytic core has been determined via the repeating distance of 2D array. We expect that the same strategy can generally be applicable for studying other nucleic acid structures.
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- PAR ID:
- 10323885
- Date Published:
- Journal Name:
- Chemical Communications
- ISSN:
- 1359-7345
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D2CC01144A
