The statistical dynamics of partially incoherent ultrafast lasers are complex and chaotic,which is significant for fundamental research and practical applications.We experimentally and theoretically reveal the statist...The statistical dynamics of partially incoherent ultrafast lasers are complex and chaotic,which is significant for fundamental research and practical applications.We experimentally and theoretically reveal the statistical dynamics of the spectral evolutions and correlations in an incoherent noise-like rectangle pulse laser(NLRPL).Based on statistical histogram analysis,the probability distribution asymmetry of the spectral intensity fluctuation is decayed with the wavelength far away from the spectral peak due to the detection noise.The full-spectral correlation values indicate that the spectral similarity between two round trips is exponentially weakened as the round-trip offset increases.By studying the correlation map of spectral components,we find that the area of the high-correlation region is relevant to the pump power,which is reduced by increasing the pump power.The mutual information of the spectra demonstrates that two spectral components with symmetry about the spectral peak have a statistical dependence.Experimental observations and statistical properties can coincide well with theoretical numerical simulations.We reveal the pump-dependent spectral correlation of the NLRPL and provide multiple statistical methods for the characterizations of chaotic dynamics in incoherent light sources.展开更多
This article presented a facile fabrication process for polydimethylsiloxane(PDMS)composite gold nanotris⁃octahedra(Au NTOH)for a flexible SERS sensor with high sensitivity.Specifically,Au NTOH with excellent SERS beh...This article presented a facile fabrication process for polydimethylsiloxane(PDMS)composite gold nanotris⁃octahedra(Au NTOH)for a flexible SERS sensor with high sensitivity.Specifically,Au NTOH with excellent SERS behaviors was synthesized using a seed-mediated growth method and the dimensions of the Au NTOH was easily tuned.In addition,the influence of size on the SERS performance of their monolayers was systematically investigated,and the Au NTOH with the size of 61 nm possessed the best SERS performance.Importantly,a hydrophilic-substrateassisted interfacial self-assembled monolayer transfer technique was proposed to transfer Au NTOH onto PDMS films,resulting in forming flexible and transparent Au NTOH@PDMS substrates.Furthermore,the excellent signal homoge⁃neity of this substrate was demonstrated and the sensitivity was verified by a measurement of crystal violet(CV)as low as 1×10^(-8) mol/L.As a result,this SERS sensor is progressing for applying in the identification of trace contaminants in broad fields.展开更多
基金support from the National Key R&D Program of China(Grant No.2020YFB1805901)the National Natural Science Foundation of China(Grant No.62105274)+1 种基金the Technology and Innovation Commission of Shenzhen Municipality(Grant No.JCYJ20210324133406018)the Research Grants Council,University Grants Committee of Hong Kong SAR(Grant No.PolyU15301022).
文摘The statistical dynamics of partially incoherent ultrafast lasers are complex and chaotic,which is significant for fundamental research and practical applications.We experimentally and theoretically reveal the statistical dynamics of the spectral evolutions and correlations in an incoherent noise-like rectangle pulse laser(NLRPL).Based on statistical histogram analysis,the probability distribution asymmetry of the spectral intensity fluctuation is decayed with the wavelength far away from the spectral peak due to the detection noise.The full-spectral correlation values indicate that the spectral similarity between two round trips is exponentially weakened as the round-trip offset increases.By studying the correlation map of spectral components,we find that the area of the high-correlation region is relevant to the pump power,which is reduced by increasing the pump power.The mutual information of the spectra demonstrates that two spectral components with symmetry about the spectral peak have a statistical dependence.Experimental observations and statistical properties can coincide well with theoretical numerical simulations.We reveal the pump-dependent spectral correlation of the NLRPL and provide multiple statistical methods for the characterizations of chaotic dynamics in incoherent light sources.
基金The National Natural Science Foundation of China(12274055)the Fundamental Research Funds for the Central Universities(04442024072)the Training Program of Innovation and Entrepreneurship for Undergraduates in Dalian Minzu University(202312026063)。
文摘This article presented a facile fabrication process for polydimethylsiloxane(PDMS)composite gold nanotris⁃octahedra(Au NTOH)for a flexible SERS sensor with high sensitivity.Specifically,Au NTOH with excellent SERS behaviors was synthesized using a seed-mediated growth method and the dimensions of the Au NTOH was easily tuned.In addition,the influence of size on the SERS performance of their monolayers was systematically investigated,and the Au NTOH with the size of 61 nm possessed the best SERS performance.Importantly,a hydrophilic-substrateassisted interfacial self-assembled monolayer transfer technique was proposed to transfer Au NTOH onto PDMS films,resulting in forming flexible and transparent Au NTOH@PDMS substrates.Furthermore,the excellent signal homoge⁃neity of this substrate was demonstrated and the sensitivity was verified by a measurement of crystal violet(CV)as low as 1×10^(-8) mol/L.As a result,this SERS sensor is progressing for applying in the identification of trace contaminants in broad fields.
