32 results about "Photon upconversion" patented technology

The invention discloses a photon upconversion method and system based on microwave frequency quadruplication and belongs to the field of microwave photonics. Optical carriers generated by a laser areinput into a first double-parallel Mach-Zehnder modulator. An upper arm submodulator is modulated through utilization of local oscillator signals. Through adjustment of direct current bias of the modulator, the modulator is enabled to work a carrier suppressed maximum transmission point. Modulated optical signals enter a fiber bragg grating through an optical circulator. Through utilization of wavelength selectivity of the fiber bragg grating, positive second-order optical sidebands of a local oscillator are transmitted and are taken as carriers to enter a second double-parallel Mach-Zehnder modulator. Negative second-order optical sidebands of the local oscillator are reflected and are collected through utilization of the optical circulator. Intermediate frequency signals are loaded to the second double-parallel Mach-Zehnder modulator through utilization of a 90-dgree electric bridge, and carrier suppressed single-sideband modulation is realized through utilization of the direct current bias. Two optical paths are combined, power amplification is carried out on the optical signals, and insertion losses of the modulator are compensated. Frequency beating is carried out through utilization of a photoelectric detector, thereby obtaining frequency quadruplicated upconversion signals.

The invention provides a medium and a method for protecting a triplet excited state of a photosensitizer by photochemically removing oxygen and application. The medium is polyvinylpyrrolidone. The method comprises the steps of mixing PVP, the photosensitizer and a solvent, standing to form gel, and irradiating the gel by virtue of a laser method. According to the method, the situation that phosphorescence is quenched by oxygen in air is prevented; and the method is applied to the fields of observation and test experiments for photophysical and photochemical processes, the conversion of photoetching or triplet state-triplet state annihilation photons and the like.

The invention provides a method for removing oxygen through photochemistry to protect triplet excited state of a photosensitizer and application thereof. The method comprises the following steps: adding the photosensitizer into a solvent, and irradiating a solvent containing the photosensitizer by using exciting light. Through the method, the solvent does not need to be subjected to oxygen removalmeasures such as bubbling through inert gas and the like; the oxygen in the solvent can be removed by directly irradiating the solvent containing the photosensitizer under the air condition; phosphorous light is gradually intensified in the solvent; the invention also relates to the application of the method to photoetching through gel and implementation of triplet state-triplet state annihilation photon up-conversion under the air condition.

An optical device for steering radiation comprises a superprism structure a negative index of refraction for electromagnetic radiation having a frequency of 2ω only, and a photon upconversion structure disposed to upconvert a portion of incident electromagnetic radiation having a frequency of ω to electromagnetic radiation having a frequency of 2ω and to couple a portion of the incident electromagnetic radiation having a frequency ω and the upconverted electromagnetic radiation having a frequency of 2ω into the superprism structure.

The invention relates to an ultra-strong multi-photon up-conversion nanocrystalline for super-resolution imaging. The ultra-strong multi-photon up-conversion nanocrystalline for super-resolution imaging is a hexagonal crystal monodisperse sodium yttrium tetrafluoro nanocrystalline with the average grain diameter of 20-50nm and rare earth ytterbium ions and thulium ions are co-doped in the nanocrystalline. The molar dosage concentration of ytterbium ions is 10-49% while the molar dosage concentration of thulium ions is 0.1-2%. The ultra-strong multi-photon up-conversion nanocrystalline for super-resolution imaging provided by the invention has the advantages that the monodisperse sodium yttrium tetrafluoro nanocrystalline which is prepared by way of nucleation/growth separation, rare earth ion type selection and dosage concentration regulating method has the characteristics of being uniform and controllable in side and shape, capable of generating ultra-strong multi-photon up-conversion luminescence and suitable for super-resolution imaging.

Described herein are materials and systems for efficient upconversion of photons. The materials may be disposed in a system comprising two semiconductor materials with an interface therebetween, the interface comprising a valence and/or conduction band offset between the semiconducting materials of about −0.5 eV to about 0.5 eV, including 0, wherein one of the semiconductor materials is a material with discrete energy states and the other is a material with a graded composition and/or controlled band gap. The system can upconvert photons by: a) controlling energy levels of discrete energy states of a semiconducting material in a system to direct tunneling and exciton separation; b) controlling a compositional profile of another semiconducting material in the system to funnel charges away from an upconversion region and into a recombination zone; and c) utilizing the discrete energy states of the semiconducting material in the system to inhibit phonon relaxation.

The invention discloses a category of heterofluorene derivatives with strong two photon absorption character characterized in that, it is prepared from the symmetrical conjugation molecular by using the heterocyclic fluorine as the center of symmetry, wherein the hetero atoms in the heterocyclic fluorine are selected from S, O or N, and N atom has straight chain or branched chain alkyl, the elementary oxdiazole with electron suction capability is selected as the branch to construct conjugation multiple branch molecular material.

A testing device for a photon upconverter frequency response comprises a computer control module, an optical pulse generating module, a voltage-stabilized source, a photon upconverter, a photoelectric detector and a sampling oscilloscope. The input end of the optical pulse generating module is connected with one output end of the computer control module. The input end of the voltage-stabilized source is connected with the other output end of the computer control module. One input end of the photon upconverter is connected with the output end of the voltage-stabilized source. An optical response area of the photoelectric detector receives the optical output signals of the photon upconverter. One input end of the sampling oscilloscope is connected with the output end of the photoelectric detector, the other input end of the sampling oscilloscope is connected with the other output end of the optical pulse generating module, and the output end of the sampling oscilloscope is connected with the input end of the computer control module. According to the device, the frequency response characteristics of photon upconverters of the series can be detected and analyzed, a detecting means and an analysis tool are provided for manufacturing of a photon upconverter with higher response speed, and a foundation is laid for the study of a high-speed infrared imaging device. The invention further provides a testing method for the photon upconverter frequency response.

A composition includes a photon upconversion nanoparticle coupled to a photosensitizer nanoparticle that can absorb light and convert tissue oxygen into reactive oxygen species. A low temperature hydrothermal method of making photon upconversion nanoparticles includes dispersing Yb(NO₃)₃, Y(NO₃)₃, and Er(NO₃)₃ in water to prepare a mixture; adding an ethylenediaminetetraacetic acid and NaF with sonication to make a solution; adjusting a pH of the solution to approximately 3.5 using HNO₃ and NaOH; treating the solution hydrothermally at approximately 130° C. for approximately 4 hours; quenching to approximately 20° C.; collecting and washing the photon upconversion nanoparticles. A near infrared triggered photon upconversion method for synergistic photodynamic and photothermal cancer therapy includes administering a nanocomposite comprising a photon upconversion nanoparticle coupled to a photosensitizer nanoparticle that can absorb light and convert tissue oxygen into reactive oxygen species; and exposing the mammal and the nanocomposite to a near infrared source of actinic radiation.