5 results about "Local field enhancement" patented technology

This invention discloses a hydrogen sensing probe and its fabrication method. The nanowire array of this invention provides a high specific surface area and a three-dimensional channel structure, improving the contact efficiency between the sensitive layer and hydrogen, providing a pathway for light / gas transmission, and balancing sensitivity and response / recovery kinetics. At the same time, it abandons the traditional external cavity mirror structure. The Fabry-Perot interferometer cavity formed by the second and first reflective layers enhances the round-trip interaction between light and the sensitive layer, improves the spectral drift amplitude and signal-to-noise ratio, and reduces the influence of environmental factors. Furthermore, the nanowire array is coupled with the emitted light field and / or reflected light field at the end face to form a local field enhancement effect, which is superimposed with the Fabry-Perot interferometer effect, resulting in a larger spectral shift caused by the same amount of hydrogen.

The invention belongs to the technical field of blood sodium in-vivo detection, and particularly relates to a non-invasive in-vivo blood sodium concentration detection system and a non-invasive in-vivo blood sodium concentration detection method which are combined with a terahertz spectrum technology and photoacoustic microscopic imaging. According to the invention, through short-wave photoacoustic microscopic imaging, high-spatial-resolution positioning of subcutaneous microvessels is realized, and accurate coordinates are provided for targeted detection; meanwhile, through a double-pulse differential photoacoustic detection technology, terahertz photoacoustic response from blood sodium ions is specifically extracted from complex tissue signals, and the strong water background is effectively inhibited; by introducing the terahertz local field enhancement module, the energy loss is compensated while the hyperspectral specificity is ensured by adopting narrow-band filtering, and the detection sensitivity is remarkably improved.

The application relates to a low-threshold plasmonic graphene all-optical nonlinear activator, which comprises a substrate, a gold film is covered on the substrate, a device pattern is etched on the gold film, and a graphene film is covered on the gold film. The gold film pattern of the plasmonic structure can generate a very strong local field enhancement effect, significantly enhancing the interaction between light and graphene; by utilizing the Pauli blocking effect and the ultrafast carrier dynamics of graphene, combining the local field enhancement effect of the plasmonic structure to strengthen the light-matter interaction, low-threshold nonlinear activation is realized. The device activation threshold is as low as 7.03 nW, and the accuracy in MNIST handwritten digit recognition is 96.7%; by eliminating the photoelectric conversion link, a low-power-consumption, high-energy-efficiency optical domain processing scheme is provided, and the practicability of optical neural network calculation is significantly improved.

The invention provides a method for forming elastic strain through laser shock to enhance the electrical property of a two-dimensional material, and belongs to the technical field of laser nanoscale processing of semiconductor transistors. The method comprises the following steps: firstly, transferring metal nanoparticles prepared in advance to a substrate containing a two-dimensional material, and further preparing a polymer film layer on the metal nanoparticles; stripping the obtained sample from the substrate, turning over the sample, and transferring the sample to a target substrate; and finally, pulse laser shock is used for treatment, so that the metal nanoparticles protrude relative to the upper surface of the polymer film, and the two-dimensional material obtains stable elastic strain. According to the method, the two-dimensional material can obtain stable elastic strain in the photoelectric transistor including but not limited to flexibility, the local field of the LSPR of the metal nanoparticles enhances the two-dimensional material cooperating with the elastic strain, so that the light absorption range of the prepared photoelectric transistor is enlarged, and the electrical property is remarkably improved; therefore, the flexible electronic device with high photoresponsiveness and outstanding electrical properties is manufactured.

The invention discloses a hydrogen sensing probe and a preparation method thereof.A nanowire array provides a high specific surface area and a three-dimensional channel structure, the contact efficiency of a sensitive layer and hydrogen is improved, a path is provided for light / gas transmission, sensitivity and response / recovery kinetics are considered, meanwhile, a traditional additional endoscope structure is abandoned, and the hydrogen sensing probe has the advantages that the structure is simple, the cost is low, and the application range is wide. A Fabry-Perot interference cavity formed by the second reflecting layer and the first reflecting layer enhances the back-and-forth interaction between light and the sensitive layer, improves the spectrum drift amplitude and the signal-to-noise ratio and reduces the influence of environmental factors, and the nanowire array is coupled with an end face emergent light field and / or a reflecting light field to form a local field enhancement effect, so that the detection sensitivity is improved. And superposition with a Fabry-Perot interference effect is carried out, so that the change caused by the same hydrogen generates larger spectrum shift.