Publications by authors named "Haiyao Yang"

An optical spectrometer is a basic spectral instrument that probes microscopic physical and chemical properties of macroscopic objects but generally suffers from difficulty in broadband time-resolved measurement. In this work, we report the creation of ultrabroadband white-light laser with a 3-dB bandwidth covering 385 to 1,080 nm, pulse energy of 1.07 mJ, and pulse duration of several hundred femtoseconds by passing 3-mJ pulse energy, 50-fs pulse duration Ti:Sapphire pulse laser through a cascaded fused silica plate and chirped periodically poled lithium niobate crystal.

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Surface-enhanced Raman spectroscopy (SERS) is a vibrational spectroscopy technique that enables specific identification of target analytes with sensitivity down to the single-molecule level by harnessing metal nanoparticles and nanostructures. Excitation of localized surface plasmon resonance of a nanostructured surface and the associated huge local electric field enhancement lie at the heart of SERS, and things will become better if strong chemical enhancement is also available simultaneously. Thus, the precise control of surface characteristics of enhancing substrates plays a key role in broadening the scope of SERS for scientific purposes and developing SERS into a routine analytical tool.

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Carbon dots (CDs) have been studied for years as one of the most promising fluorescent nanomaterials. However, CDs with red or solid-state fluorescence are rarely reported. Herein, through a one-pot solvothermal treatment, hydrophobic CDs (H-CDs) with blue dispersed emission and red aggregation-induced emission are obtained.

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Different from their bulk counterparts, plasmonic molybdenum oxide nanomaterials display superior optical and electronic properties, but unfortunately, phase-controlled synthesis of molybdenum oxide nanomaterials with multifunctional performances still remains a challenge. To actualize this, a surfactant-free solvothermal strategy was proposed to fabricate molybdenum oxide nanomaterials with a tunable phase. Encouragingly, the as-prepared molybdenum dioxide nanoparticles (MoO2 NPs) exhibit intense near-infrared (NIR) absorption attributed to the localized surface plasmon resonance (LSPR) effect, which results in their application as a surface enhanced Raman scattering (SERS) substrate to detect trace amounts of molecular species including Rhodamine 6G (R6G), crystal violet (CV), IR-780 iodide (IR780) and methylene blue (MB).

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