Method for preparing cascade enhanced SERS substrate by means of double-pulse vortex femtosecond laser

A femtosecond laser and double-pulse technology, which is applied in the field of laser applications, can solve the problems of weak Raman detection signal strength, and achieve the effects of improving near-field enhancement capabilities, improving reflectivity, and optimizing energy deposition

Inactive Publication Date: 2021-08-20
BEIJING INSTITUTE OF TECHNOLOGYGY
View PDF3 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to solve the problem of weak Raman detection signal intensity of low-concentration molecules, and to provide a method for preparing a cascade-enhanced SERS substrate with a double-pulse vortex femtosecond laser

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for preparing cascade enhanced SERS substrate by means of double-pulse vortex femtosecond laser
  • Method for preparing cascade enhanced SERS substrate by means of double-pulse vortex femtosecond laser
  • Method for preparing cascade enhanced SERS substrate by means of double-pulse vortex femtosecond laser

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0029] The optical path system for realizing dual-pulse vortex femtosecond laser shaping is as follows: image 3 shown. First, load the vortex phase on the two reflective spatial light modulators, shape the two beam-split Gaussian laser beams into a vortex beam, and adjust the shaped vortex pulse by adjusting the optical path difference between the two beam-splitting optical paths time domain delay. In this example, the pulse implementation is 40ps. Subsequently, the laser light passes through lenses 1 and 2 (f 1 = f 2 =500mm) to achieve phase transfer and avoid phase distortion and beam deformation during beam propagation. Then focus through a 50X (NA=0.8) objective lens, and process the sample placed on the translation stage. The sample used in this example is single crystal silicon.

[0030] In this example, the energy of the two sub-pulses is equal, both 15nJ, the laser pulse repetition frequency is 1kHz, and the moving speed of the displacement platform is 2000μm / s....

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention relates to a method for preparing a cascade enhanced SERS substrate by means of double-pulse vortex femtosecond laser, and belongs to the technical field of laser application. The SERS substrate prepared by the method is composed of three structures of noble metal nanoparticles, a micro needle tip and a micro lens. Firstly, a micro concave surface-micro needle tip composite structure is prepared on a silicon surface by means of a vortex pulse sequence subjected to space-time collaborative shaping, and the curvature of the micro concave surface is flexibly adjusted through adjustment of pulse delay to optimize deposition of laser energy. Through subsequent noble metal film deposition, the reflectivity of the micro concave surface structure is greatly improved, the micro concave surface structure can be used as a focusing micro-lens, and a large number of noble metal nano-particles can be attached to the surface of the micro needle tip. Incident laser is converged to the top end of the micro needle tip by adjusting the curvature of the micro concave surface, and the local laser energy density near the micro needle tip is improved, so that the local surface plasma resonance intensity of nano-particles of the needle tip is improved, a cascade enhancement effect is achieved, and the purpose of improving the Raman scattering signal intensity is achieved.

Description

technical field [0001] The invention relates to a method for preparing a cascade enhanced SERS substrate with a double-pulse vortex femtosecond laser, and belongs to the technical field of laser applications. Background technique [0002] Raman spectroscopy uses the scattering signal generated when the laser is irradiated on the surface of the target molecule to reveal the molecular structure information of the detected substance. It has high sensitivity and is widely used in the field of biological analysis. However, when the concentration of target molecules is low, the returned Raman spectrum signal is very weak, resulting in the inability to accurately obtain the structural information of low-concentration molecules. In 1977, researchers found that the Raman spectrum signal of pyridine molecules attached to the surface of a rough silver electrode was significantly enhanced compared with that of pyridine molecules dispersed in solution, and attributed this to the localize...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C23C14/30C23C14/16C23C14/02G01N21/65
CPCC23C14/30C23C14/16C23C14/022G01N21/658G01N21/65G01N2021/655
Inventor 姜澜李晓炜周世鹏高帅黄骥
Owner BEIJING INSTITUTE OF TECHNOLOGYGY
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap