38 results about "Magnetic circular dichroism" patented technology

An optical parameter measuring apparatus for measuring optical parameters of an object includes a light source, a polarizing module, a Stokes polarimeter and a calculating module. The light source emits a light which is polarized by the polarizing module and received by the Stokes polarimeter. According to the light information generated by the Stokes polarimeter, Mueller matrixes of linear birefringence, circular birefringence, linear dichroism, circular dichroism and linear / circular depolarization of the object, and Stokes vector established according to the Mueller matrixes, the calculating module calculates the optical parameters.

This invention relates to a device for calibrating circular or linear dichroism spectrometers, or other photoelastic modulator (PEM) based devices or instruments. In preferred embodiments, the present invention features a device for calibrating circular dichroism or linear dichroism spectrometers comprising at least one waveplate (Q) providing (n±¼) waves of retardation at a defined set of wavelengths, and at least one isotropic plate (P). The invention also features methods for using the device, for example, for calibrating circular dichroism spectrometers or linear dichroism spectrometers.

A reflection surface 12 constituted by a transition metal having a core level absorption edge in the vicinity of a wavelength of a soft X-ray is formed on an inside of a vacuum vessel 14, and furthermore, there is provided a permanent magnet 13 for generating a magnetic field in a perpendicular direction to a longitudinal direction of the vacuum vessel 14 in a position of the reflection surface 12 by which the soft X-ray is to be reflected, and the soft X-ray to be linearly polarized light incident on the vacuum vessel 14 is reflected at plural times over the reflection surface 12 in a position where the magnetic field is applied in such a manner that magnetic scattering is increased by a resonant effect of a magnetic circular dichroism when the soft X-ray is reflected by the reflection surface 12. Thus, a great difference in a refractive index is made between circularly polarized counterclockwise light and circularly polarized clockwise light which constitute the linearly polarized light, and a phase difference between the circularly polarized counterclockwise light and the circularly polarized clockwise light is obtained at a time. Consequently, it is possible to reversibly convert the soft X-ray from the linearly polarized light into the circularly polarized light or from the circularly polarized light into the linearly polarized light by a reflection to be carried out at only several times.

The invention discloses a method for detecting L-cysteine concentration by applying of a circular dichrorism, and belongs to the technical field of analytical chemistry. The L-cysteine and a reagent are mixed according to a certain volume ratio to generate self-assembly and form gold nanoparticle dimer, reactant is placed on a circular dichroism analyzer, signal strength at 525nm position of a main wave is detected, and therefore the concentration of the L-cysteine is measured. Compared with a traditional instrument, under a liquid environment, AuNPs and the L-cysteine are utilized to react to form the gold nanoparticle dimer, the chirality of the L-cysteine can be enlarged through the form of a binary assembly, and a CD signal is produced by the gold nanoparticle diamer in a visible region. The contents of the L-cysteine are measured by a manner that the CD signal intensity under the liquid environment is measured through the circular dichrorism. The method only can be carried out under the liquid environment, and a step of washing is not needed. Only one step of reaction is needed, reaction conditions are simplified, and sensitivity of detection is improved.

The invention provides a method for preparing an all-dielectric ultra-thin two-dimensional circular polarization dichroic device, being able to realize the effect of directly generating circularly polarized light and distinguishing left and right rotary circularly polarized light. The structure includes a substrate and Z type through holes which are covered on the substrate and etched in a dielectric layer. The polarizer of the all-dielectric ultra-thin two-dimensional circular polarization dichroic device has an average circular dichroism of more than 70% in the 1.50 mu m to 1.61 mu m wave band, can reach a maximum circular dichroism to 98.3% at 1.53 mu m, and has characteristics of being wider in the wave band, being simple in structure and being easy to manufacture feature, and having agreat application value in future optical sensing systems, advanced nanophotonic devices and integrated optical systems.

The invention discloses a system for synchronously measuring a polar magneto-optic Kerr spectrum and a magnetic circular dichroism spectrum, comprising a liquid helium refrigerator, a low-temperature superconducting magnet system, a super-continuous white light source, a monochromator, a chopper, two Glan-Taylor prisms, a photoelastic modulator, a broadband depolarizing beam splitter prism, an achromatic lens, a silicon detector, three lock-in amplifiers and a computer. With the system provided by the invention, the polarized magneto-optic Kerr (KERR) spectrum and the magnetic circular dichroism (MCD) spectrum of a sample can be simultaneously measured, so that the magnetism, as well as energy band structure and properties related to spinning of substances can be further studied.

A circular dichroism (CD) spectrometer includes an alignment mechanism that automatically adjusts the elements thereof at appropriate positions. The spectrometer has a focusing-lens position-and-orientation adjustment mechanism which adjusts the position and the orientation of the detector-side focusing lens. It also has a detector rotation mechanism which adjusts the orientation of the detector. Firstly, a control PC monitors the CD spectrum of D form of optical enantiomers, and the adjustment mechanism adjusts the focusing lens such that the monitored CD spectrum matches the reference spectrum related to the D form. Next, the control PC moniters CD spectrum of L form of optical enantiomers, and the adjustment mechanism adjusts the focusing lens such that the monitored CD spectrum of the D and L forms become symmetrical. And, the rotation mechanism adjusts the orientation of the detector such that the intensity of the detector signal is maximized.

The invention discloses a chiral metal nanostructure realizing circular dichroism and a preparation method thereof. The preparation method comprises performing evaporation of A and B materials in a rotating alternative manner according to a clockwise or anti-clockwise direction on a template with polystyrene pellets as a substrate, to form an AB alternative helical structure, wherein the A is an insulator material and B is a metal material. Through measurement of light normal incidence and / or oblique incidence, the chiral metal nanostructure is proved to have relatively high circular dichroism. The technical scheme is simple in operation, and more accurate in measuring signals. The chiral metal nanostructure can be applied in biological monitoring, enantiomer sensing, polarization conversion, and photoelectronic circuit polarizers.

The invention discloses a method for high-sensitivity detection of silver ions through circular dichroism, belonging to the technical field of analytic chemistry. The method comprises the following steps: respectively coupling gold nanoparticles with two different grain sizes and two specific nucleic acids rich in a cytosine (C) sequence to obtain AuNPs10nm-DNA1 and AuNPs25nm-DNA2, adding silver ions to cause AuNPs10nm-DNA1 and AuNPs25nm-DNA2 to generate C-Ag<+>-C mispairing identification, reducing through trisodium citrate, reacting AuNPs10nm-DNA1, AuNPs25nm-DNA2 and silver ions under the liquid environment to form a binary assembly so as to form plasma chirality, and causing the gold nanoparticles to generate a circular dichroism CD signal in a visible region. The CD signal intensity in the liquid environment is measured through the circular dichroism so as to measure the content of the silver ions. According to the invention, reaction is only performed in the liquid environment, a step of cleaning is unnecessary, one-step reaction is only required, the reaction condition is simplified, the sensitivity of detection is improved, and the leading level in the world is achieved.