36 results about "Reciprocal lattice" patented technology

The invention provides a small optical device with which incident light can be demultiplexed. The optical device includes a demultiplexing portion 4 (first optical member) separating TE waves and TM waves of incident light of a wavelength lambda and an optical fiber 1 (optical input portion) inputting incident light into the demultiplexing portion 4. The demultiplexing portion 4 has a periodically changing refractive index. The angle defined by the first reciprocal lattice vector alpha1 and the second reciprocal lattice vector alpha2 of the demultiplexing portion 4 at the wavelength lambda is not greater than 90°. In the direction of the first reciprocal lattice vector alpha1 the wave number of the TE wave is larger than the wave number of the TM wave. In the direction of the second reciprocal lattice vector alpha2 the wave number of the TE wave is smaller than the wave number of the TM wave. The optical fiber 1 inputs the incident light in a direction that is parallel to a plane including the first reciprocal lattice vector alpha1 and the second reciprocal lattice vector alpha2.

The invention provides a small optical device with which incident light can be demultiplexed. The optical device includes a demultiplexing portion 4 (first optical member) separating TE waves and TM waves of incident light of a wavelength lambd and an optical fiber 1 (optical input portion) inputting incident light into the demultiplexing portion 4. The demultiplexing portion 4 has a periodically changing refractive index. The angle defined by the first reciprocal lattice vector alpha1 and the second reciprocal lattice vector alpha2 of the demultiplexing portion 4 at the wavelength lambd is not greater than 90°. In the direction of the first reciprocal lattice vector alpha1 the wave number of the TE wave is larger than the wave number of the TM wave. In the direction of the second reciprocal lattice vector alpha2 the wave number of the TE wave is smaller than the wave number of the TM wave. The optical fiber 1 inputs the incident light in a direction that is parallel to a plane including the first reciprocal lattice vector alpha1 and the second reciprocal lattice vector alpha2.

The present invention is a method for measuring an amount of strain of a bonded strained wafer in which at least one strained layer is formed on a single crystal substrate by a bonding method, wherein at least, the bonded strained wafer is measured with respect to two asymmetric diffraction planes with diffraction plane indices (XYZ) and (−X−YZ) by an X-ray diffraction method, a reciprocal lattice space map is created from the measured data, and the amount of strain of the strained layer is calculated from the peak positions for the respective diffraction planes of the single crystal substrate and the strained layer appearing on the reciprocal lattice space map. Thereby, there can be provided a method for measuring an amount of strain by which amounts of strain in the horizontal direction and in the vertical direction of the strained layer by an X-ray diffraction method in a bonded strained wafer can be measured in a shorter time and more simply.

A method and an apparatus for analyzing a twinned crystal can display three-dimensionally the real space unit lattice, the reciprocal space primitive lattices and the reciprocal lattice points of each component of the twinned crystal. Respective crystal orientation matrices of the plural components of the twinned crystal are obtained with the use of X-ray single crystal structure analytical equipment. The first computing means finds the real-space unit lattices of the plural components based on the crystal orientation matrices and creates display data for displaying them three-dimensionally with possible their rotation, scaling up and down and translation. The second computing means finds the reciprocal-space primitive lattices and creates display data for displaying them three-dimensionally. The third computing means creates display data for displaying three-dimensionally reciprocal lattice points causing X-ray diffraction with a distinction between the components of the twinned crystal.

In a method for measuring an amount of strain of a bonded strained wafer, at least one strained layer is formed on a single crystal substrate. The bonded strained wafer is measured with respect to two asymmetric diffraction planes with diffraction plane indices (XYZ) and (−X−YZ) by an X-ray diffraction method, a reciprocal lattice space map is created from the measured data, and the amount of strain of the strained layer is calculated from the peak positions for the respective diffraction planes of the single crystal substrate and the strained layer appearing on the reciprocal lattice space map. Thereby, amounts of strain in the horizontal direction and in the vertical direction of the strained layer can be measured in a shorter time and more simply.

Provided are an electronic device and a light-receiving and light-emitting device which can control the electron configuration of a graphene sheet and the band gap thereof, and an electronic integrated circuit and an optical integrated circuit which use the devices. By shaping the graphene sheet into a curve, the electron configuration thereof is controlled. The graphene sheet can be shaped into a curve by forming the sheet on a base film having a convex structure or a concave structure. The local electron states in the curved part can be formed by bending the graphene sheet. Thus, the same electron states as the cylinder or cap part of a nanotube can be realized, and the band gaps at the K points in the reciprocal lattice space can be formed.

A magnesium oxide single crystal having controlled crystallinity has a subboundary, and ranges of variation of diffraction line positions, as measured for reciprocal lattice maps with respect to a region surrounded by the same subboundary, with the range of the variation of 1×10−3 to 2×10−2 degree of on Δω coordinates, and with the range of the variation of 4×10−4 to 5×10−3 degree on 2θ coordinates.

The invention discloses a construction method of an infrared laser in ultra quantum conversion limit based on optic superlattice. By utilizing the optic superlattice of the structure, the structure of the optic superlattice provides two reciprocal lattice vectors simultaneously, wherein one reciprocal lattice vector is used for compensating phase mismatch in an OPO (optical parametric oscillation) process from near infrared to intermediate infrared, and the other reciprocal lattice vector is used for compensating phase mismatch in a signal light pump OPA (optical parametric amplification) from the OPO process, in the process, the intermediate infrared laser which is generated in the OPO process can be amplified further, thus more efficient intermediate infrared laser output of the ultra quantum conversion limit is obtained; and a commensurability ratio double periodic structure is adopted for the optic superlattice, thus the more efficient intermediate infrared laser of the ultra quantum conversion limit is obtained.

The invention discloses a method for generating high-frequency ultrasonic waves based on a dielectric body superlattice and belongs to the field of electroacoustic energy transduction. The superlatticThe invention discloses a method for generating high-frequency ultrasonic waves based on a dielectric body superlattice and belongs to the field of electroacoustic energy transduction. The superlattice takes a piezoelectric crystal as a medium. An arranged two-dimension modulating structure provides a plurality of reciprocal lattice vectors at the same time and can realize multidirectional multi-fe takes a piezoelectric crystal as a medium. An arranged two-dimension modulating structure provides a plurality of reciprocal lattice vectors at the same time and can realize multidirectional multi-frequency and multimode ultrasound output at high frequency in an alternative electric field, wherein the ultrasonic waves at different frequency have different propagation directions and can be used irequency and multimode ultrasound output at high frequency in an alternative electric field, wherein the ultrasonic waves at different frequency have different propagation directions and can be used independently. The frequency, propagation direction and sound wave mode of high-frequency ultrasonic waves generated by the method can be designed and modulated by the two-dimension structure periodicandependently. The frequency, propagation direction and sound wave mode of high-frequency ultrasonic waves generated by the method can be designed and modulated by the two-dimension structure periodically and symmetrically. The method has the advantages of simplicity, high efficiency and integration.lly and symmetrically. The method has the advantages of simplicity, high efficiency and integration.

The invention relates to a method for setting an optical superlattice structure aiming at a coupling nonlinear optical process. Fourier transformation of a window is adopted to replace common whole fourier transformation; a local effective nonlinear coefficient and a spatial weighting function of a reciprocal lattice vector of an optical superlattice are introduced; the competitive relation between the fourier coefficients of each reciprocal lattice vector is considered; the spatial weighting function of the reciprocal lattice vector is subjected to optimized matching; for a triple-frequency coupling process, the spatial weighting function of the reciprocal lattice vector leans to the reciprocal lattice vector of the frequency doubling process in the initial stage and leans to the reciprocal lattice vector of the sum frequency process in the late stage; and through the optimization of the spatial distribution of the local fourier coefficients of two reciprocal lattice vectors, the method realizes the optimization of nonlinear conversion efficiency in the coupling process and carries out the setting of the optical superlattice structure on the basis.

Exemplary methods for aligning spectrometers are described herein. The spectrometer includes a radiation source, a crystal analyzer, and a detector, all located in the instrument plane. The method includes rotating the crystal analyzer about an axis in the instrument plane and perpendicular to the plane of rotation such that (i) the reciprocal lattice vector of the crystal analyzer is in the instrument plane, or ( ii) The component of the reciprocal lattice vector in the plane of rotation is perpendicular to the instrument plane. The origin of the reciprocal lattice vectors lies on the axis. The method also includes tilting the crystal analyzer or translating the detector such that the reciprocal lattice vector bisects a line segment bounded by the detector and the radiation source. Exemplary spectrometers associated with the exemplary methods are also disclosed.

A periodic table Group 13 metal nitride crystals grown with a non-polar or semi-polar principal surface have numerous stacking faults. The purpose of the present invention is to provide a period table Group 13 metal nitride crystal wherein the occurrence of stacking faults of this kind are suppressed. The present invention achieves the foregoing by a periodic table Group 13 metal nitride crystal being characterized in that, in a Qx direction intensity profile that includes a maximum intensity and is derived from an isointensity contour plot obtained by x-ray reciprocal lattice mapping of (100) plane of the periodic table Group 13 metal nitride crystal, a Qx width at 1 / 300th of peak intensity is 6×10−4 rlu or less.