105 results about "Lattice constant" patented technology

This application relates to a monolithically integrated multi-wavelength topological cavity surface-emitting laser (PCSEL) array. According to one embodiment, a monolithically integrated PCSEL array includes multiple PCSELs formed from the same semiconductor layer, at least one layer of which is formed as a photonic crystal layer, or the laser also includes a separate photonic crystal layer. The photonic crystal layer includes multiple supercell structures, each with substructures having multiple independent one-dimensional parameters. At least two independent one-dimensional parameters of one or more substructures are modulated to be greater than or less than their equilibrium position to open the Dirac point of the supercell's bandgap at the equilibrium position. Around any point in the photonic crystal layer, the modulation of the two independent one-dimensional parameters of the supercell forms a vortex structure, which corresponds in parameter space to one or more turns around the equilibrium position. The supercell lattice constants of the two lasers can be different to emit lasers of different wavelengths.

The application provides a yttrium barium copper oxide photonic crystal and a preparation method thereof. 7‑x The photonic crystal structure is composed of periodic yttrium barium copper oxide (YBa2Cu3O 7‑x ) superconducting material circular crystal columns, the lattice constant is 2630nm, and the radius of the circular crystal column is 500nm. The photonic crystal can change the position and width of the band gap by changing the light incidence angle, so that the middle infrared band gap is realized. The photonic crystal is prepared by adopting a magnetron sputtering method to prepare a yttrium barium copper oxide film on a strontium titanate single crystal substrate, and then adopting a focused ion beam method to process the yttrium barium copper oxide film into a periodic nanostructure composed of yttrium barium copper oxide circular crystal columns, so that the yttrium barium copper oxide photonic crystal is obtained. The preparation method of the yttrium barium copper oxide photonic crystal is simple and easy to control.

The invention relates to the technical field of semiconductor materials, and discloses an III-V wafer, a preparation method of the III-V wafer, an on-chip light source and a preparation method of the on-chip light source. The III-V wafer comprises a substrate (1), an epitaxial layer (2) and a strain superlattice layer (3), wherein the epitaxial layer (2) and the strain superlattice layer (3) are sequentially arranged on the substrate (1). Wherein the strained superlattice layer (3) comprises a strained superlattice layer I (31) and a strained superlattice layer II (32), the strained superlattice layer II (32) is in contact with the epitaxial layer (2), and the lattice constant of the material of the strained superlattice layer I (31) is smaller than that of the material of the strained superlattice layer II (32). According to the III-V wafer provided by the invention, the strain superlattice layers with different lattice constants are arranged on the epitaxial layer, so that interface defects can be eliminated, the luminous efficiency of an on-chip light source is improved, the service time of the on-chip light source is prolonged, and the reliability is enhanced.

The application relates to the technical field of semiconductor material preparation, in particular to a liquid phase epitaxial growth method and equipment for dynamically regulating lattice mismatch. The specific content is as follows: a substrate is pretreated to prepare micro pits and grooves of the substrate, and a uniform solution is prepared according to phase diagram information; a temperature gradient is set in a multi-zone temperature control epitaxial furnace, and the epitaxial growth of the substrate is controlled through a boat device; the substrate and the solution pool are sequentially moved into the furnace; during the epitaxial growth process, the lattice constant error, morphology and photoelectric properties of the growth are detected, and when the detection signal deviates from the predetermined threshold, the lattice mismatch is compensated by adjusting the solution concentration and the temperature; during the displacement process, the mother liquor remaining between different layers is poured into the grooves of the substrate through the inclined substrate. The application solves the problem of lattice mismatch control by real-time detection and real-time regulation of the lattice mismatch, and improves the quality and performance of the epitaxial layer.

The hydrogen separation filter includes a porous substrate and a super lattice layer on the porous substrate. The super lattice layer includes at least one lattice expansion layer containing a first material and at least two hydrogen dissociation and permeation layers containing a second material selected from the group consisting of Pd, V, Ta, Ti, Nb, and alloys thereof. The at least one lattice expansion layer and the at least two hydrogen dissociation and permeation layers are alternately stacked. The first material and the second material have a same crystalline structure. A lattice constant a1,bulk of a first bulk material haying a same composition and a same crystalline structure as the first material and a lattice constant a2,bulk of a second bulk material having a same composition and a same crystalline structure as the second material satisfy Formula (1):1.03a2,bulk≤a1,bulk≤1.15a2,bulk  (1).

In quantum devices with Josephson junctions, the generation of TLS defects and the variation in their characteristics are suppressed. [Solution] A first superconductor film, a second superconductor film, a first insulator film, and a third superconductor film, each having a cubic crystal structure, are sequentially formed by epitaxial growth on the (100) or (111) plane of a substrate having a cubic crystal structure. The second superconductor film, the first insulator film, and the third superconductor film are patterned to form a stack including the second superconductor film, the first insulator film, and the third superconductor film. The first superconductor film is patterned using the stack as a mask. After patterning the first superconductor film, the side surfaces of the stack are wet-etched. A second insulator film is formed to cover the wet-etched side surfaces of the stack. After forming the second insulator film, a fourth superconductor film is formed in contact with the third superconductor film. The stack forms a Josephson junction, and the first superconductor film has a lattice constant between that of the substrate and that of the second superconductor film.

A method of forming a ceramic matrix composite includes arranging a plurality of fibers into a preform, each of the plurality of fibers being formed from silicon carbide, depositing a nucleating layer on the plurality of fibers, the nucleating layer comprising a crystalline material having an a-lattice constant and a c-lattice constant, and depositing a boron nitride layer on the nucleating layer. The c-lattice constant of the crystalline material of the nucleating layer corresponds to an a-lattice constant of the silicon carbide, such that the c-lattice constant of the crystalline material is within 3.0% of the a-lattice constant of the silicon carbide.

A method includes forming a fin in a substrate. The fin is etched to create a source / drain recess. A source / drain feature is formed in the source / drain recess, in which a lattice constant of the source / drain feature is greater than a lattice constant of the fin. An epitaxy coat is grown over the source / drain feature, in which a lattice constant of the epitaxy coat is smaller than a lattice constant of the fin.

A positive electrode active material for lithium-ion secondary batteries that offers high capacity and excellent charge-discharge cycle characteristics. provide. [Solution] A device containing lithium, cobalt, magnesium, oxygen, and fluorine, C Rietveld analysis was performed on the patterns obtained by powder X-ray diffraction using uKα1 rays. When this occurs, the crystal structure has a space group of R-3m, and the lattice constant of the a-axis is 2.814. Greater than ×10⁻¹⁰ m and less than 2.817 × 10⁻¹⁰ m, and c-axis The lattice constant is greater than 14.05 × 10⁻¹⁰ m, which is 14.07 × 10⁻¹⁰. When m is smaller and analyzed by X-ray photoelectron spectroscopy, the magnesium concentration when the cobalt concentration is set to 1 is... The positive electrode active material has a relative um concentration of 1.6 to 6.0.

The application discloses a chromium-doped yttrium oxide crystal material and a structural design method thereof, and belongs to the technical field of inorganic photoelectric functional crystal materials. + The crystal is of R3 trigonal crystal system minimum energy structure, Cr 9‑ The molar doping percentage is 3.125%, occupies a 1b Wyckoff site in a crystal lattice gap, forms [CrO6] 9‑ Regular octahedral coordination, Cr-O bond length is 2.073 angstrom; lattice constants a=b=10.4957 angstrom, c=18.1750 angstrom, a Γ point direct band gap is 3.23 eV, there is no virtual frequency in a phonon spectrum, dynamics is stable, simulated XRD is matched with an experimental spectrum, and Cr-O and Y-O bonds are all ionic bonds. The application realizes accurate determination of a ground state structure, stability verification and electronic property analysis by adopting CALYPSO structure prediction combined with first principle calculation, provides a standardized theoretical design process, and can be used for efficient development of photoelectric functional materials such as solid-state lasers, white light LEDs, solar cells and the like.

The invention discloses a calculation method of a rare earth oxide molecule simulation force field and a glass component modulus performance evaluation method, and the method comprises the steps: collecting parameters in a crystal database in a rare earth oxide crystal state, including lattice constants, space group numbers, stiffness matrix coefficients and density; establishing a potential energy relation model between rare earth oxide cations and oxygen atoms; fitting parameters of the potential energy relation model; constructing a rare earth oxide molecule simulation force field; collecting glass components and modulus performance data in the glass performance database; and calculating the modulus performance of the glass component by applying the rare earth oxide molecule simulation force field obtained by the calculation method of the rare earth oxide molecule simulation force field and combining a molecular dynamics simulation technology. According to the fitting method provided by the invention, the molecular simulation force field for accurately simulating the rare earth oxide can be obtained, and the Young modulus of the fiber glass containing the rare earth oxide is favorably simulated and calculated.

The invention discloses a metal intercalation boron-carbon superconducting material GeB2C2 under normal pressure and a preparation method of the metal intercalation boron-carbon superconducting material GeB2C2. The material has a two-dimensional Kagome lattice structure, the space group is P6 / mmm (No.191), the lattice constants are a = b = 2.732, and c = 16.784. Through calculation and prediction of a first principle, the material has a superconducting transition temperature of about 48 K under a normal pressure (0 GPa) condition, and is dynamically stable. The superconducting mechanism is derived from a strong electroacoustic coupling effect, and the coupling constant lambda is about 1.64. The material is composed of Ge, B and C elements rich in earth crust, the raw materials are easy to obtain, the cost is low, and the large-scale preparation potential is achieved. Compared with a traditional normal-pressure superconducting material, the material disclosed by the invention has a relatively high superconducting transition temperature; compared with a high-voltage superconductor, a high-voltage environment is not needed, and the preparation and application threshold is remarkably reduced. The material can be applied to the fields of high-performance superconducting filters, superconducting nanowire single-photon detectors, small superconducting magnets and the like, and has important scientific research values and good practical application prospects.

The invention discloses a hydrogen-based superconducting material Na2GaCuH6 with a double perovskite structure under normal pressure and a preparation method of the hydrogen-based superconducting material Na2GaCuH6. The material has an Fm-3m space group, the lattice constant is calculated and predicted through the first principle, and the material has the superconducting transition temperature of 42.04 K under the normal pressure condition. The material is composed of four common elements of Na, Ga, Cu and H, and the cost is low; the double perovskite structure is stable in thermodynamics and dynamics under normal pressure; the electro-acoustic coupling constant lambda is approximately equal to 0.98, and medium-intensity electro-acoustic coupling is achieved. Compared with an existing high-voltage hydride superconductor, the material can work without high-voltage equipment, and the preparation and application cost is greatly reduced; compared with a traditional normal-pressure superconductor, the superconductor has a higher Tc value. The material can be applied to the fields of low-temperature superconducting devices, superconducting magnets, quantum computing and the like, and has important scientific research value and application prospect.

A magnetoresistive random-access memory cell includes a templating layer. The templating layer includes a binary alloy having an alternating layer lattice structure. The cell further includes a half metallic Heusler layer including a half metallic Heusler material having a tetragonal lattice structure. The half metallic Heusler layer is located outward of the templating layer, and has a Heusler in-plane lattice constant that is different from an in-plane lattice constant in a cubic form of the half metallic Heusler material. A tunnel barrier is located outward of the half metallic Heusler layer, and a magnetic layer is located outward of the tunnel barrier.

The application discloses a vertical cavity surface emitting laser and a manufacturing method thereof. The laser comprises a GaAs substrate, a first DBR layer formed on the GaAs substrate, an oxidation layer formed on the first DBR layer, a lattice gradient layer formed on the oxidation layer, a cladding layer formed on the lattice gradient layer, wherein the cladding layer comprises a first cladding layer and a second cladding layer stacked, a gain layer formed between the first cladding layer and the second cladding layer, and a second DBR layer formed on the cladding layer. The lattice gradient layer has different lattice constants in the thickness direction, and the lattice constant of the side of the lattice gradient layer close to the GaAs substrate matches the lattice constant of the GaAs substrate, and the lattice constant of the side of the lattice gradient layer close to the gain layer matches the lattice constant of the gain layer. The vertical cavity surface emitting laser and the manufacturing method thereof can flexibly expand the lasing wavelength to 1500 nm or above.

The invention discloses a dielectric metasurface structural color device, which comprises a transparent dielectric substrate; the dielectric nano rectangular column hexagonal periodic array is arranged on the surface of the substrate, and the value range of lattice constants is shown in the specification; wherein the height, the length and the width of the medium nanometer rectangular column meet the relational expression, the length-width ratio is kept, and the length and the width are jointly optimized according to the central wavelength of a narrow-band reflection peak. The invention further discloses a structural color brightness regulation and control method. The invention solves the problem that the existing structural color and metasurface device cannot be used in the visible light reflection type structural color implementation process; the problems that the color purity is limited due to the reflection spectrum line width, the parameter design of different color pixels lacks a computable resonance positioning rule, and the continuous brightness modulation capability is insufficient under the condition that the hue is kept stable generally exist.

A piezoelectric material and a piezoelectric device. The piezoelectric material includes: a matrix, wherein a crystal structure of the matrix is an ABO3-type perovskite structure, the perovskite structure includes a rhombohedral structure and a tetragonal structure that coexist, and the matrix is near a morphotropic phase boundary; and a doping element, wherein the doping element is for replacing an A-site element or a B-site element in the perovskite structure, or filling a space in the perovskite structure, and the doping element is for increasing a difference between a lattice constant of the rhombohedral structure and a lattice constant of the tetragonal structure.

The invention discloses a method for regulating and controlling the lattice structure and the physical property of perovskite oxide based on oxygen vacancy, and the prepared perovskite oxide film has the continuous regulation and control characteristic of anisotropic physical property compared with the conventional directly grown perovskite oxide film. The method has important application value in the fields of magnetism, electricity, optics and the like of perovskite oxide thin film material regulation and control. The method comprises the following steps: firstly, controlling the growth oxygen pressure of the perovskite oxide thin film, so that the thin film is subjected to lattice expansion and relaxation at high temperature and low oxygen pressure; after growth, the perovskite oxide film is subjected to low-temperature annealing in oxygen to fill oxygen vacancies and repair crystal lattices, so that the unit cell volume is reduced. The in-plane lattice is constrained by the substrate, so that the out-plane lattice constant is obviously shrunk. Finally, the obtained perovskite oxide thin film realizes anisotropic continuous regulation and control of the lattice structure and the physical property under the condition of keeping relatively high crystal quality. According to the invention, through an innovative'oxygen vacancy introduction-elimination 'process route, a new way is provided for regulating and controlling the anisotropy of the physical property of the perovskite oxide film.

A surface coated cutting tool comprises a substrate and a coating layer, where (a) the coating layer comprises a complex nitride or carbonitride layer; (b) the complex nitride or carbonitride is (AlXVYT1-X-Y)(CαN1-α) (wherein the average values Xavg, Yavg and αavg of X, Y and α, satisfy the relations: 0.600≤Xavg≤0.950, 0.010≤Yavg≤0.300, 0.610≤Xavg+Yavg≤0.990 and 0.0000≤αavg≤0.0050); (c) the complex nitride or carbonitride comprises crystal grains containing a variable amount X of Al, wherein the average Xmax of the maxima Xmax* and the average Xmin of the minima Xmin* of X in the crystal grains satisfy the relations: 0.020≤Xmax−Xmin≤0.400, and 0.020≤Xmax−Xmin≤0.400, and (d) A* (nm)=0.404Xavg+0.4130Yavg+0.4242 (1−Xavg−Yavg) and the lattice constant A (nm) calculated from an XRD pattern satisfy the relation: |A−A*|<0.0010 (nm).

The invention discloses an optical waveguide and a three-channel wavelength division multiplexer. The three-channel wavelength division multiplexer comprises a waveguide interface, a first energy valley photonic crystal and a second energy valley photonic crystal, the first energy valley photonic crystal is formed by periodically arranging a plurality of first regular hexagonal unit cells by taking a lattice constant as a period length, the single first regular hexagonal unit cell has C3v rotational symmetry, and a first silicon dielectric cylinder and a second silicon dielectric cylinder are arranged at the upper vertex and the lower vertex of the first regular hexagonal unit cell; the second energy valley photonic crystal is formed by periodically arranging a plurality of second regular hexagonal unit cells by taking a lattice constant as a period length, the single second regular hexagonal unit cell has C3v rotational symmetry, and the upper vertex and the lower vertex of the second regular hexagonal unit cell are a second silicon dielectric cylinder and a first silicon dielectric cylinder; the side length of the first silicon dielectric cylinders is larger than that of the second silicon dielectric cylinders, so that K points of the first regular hexagonal unit cells and K points of the second regular hexagonal unit cells in the same energy band have opposite vortex chirality. The energy valley photonic crystal provided by the invention has C3 symmetry and higher stability.

This allows for even greater spin-orbit torque to be generated in SrRuO3. [Solution] This current-induced magnetization reversal element comprises a substrate 101 and a thin film 102 made of SrRuO3 crystals epitaxially grown on the substrate 101. The substrate 101 is made of a crystal whose lattice constant differs by 0.5% or more from the lattice constant of the pseudo-cubic crystal of SrRuO3, and whose main surface on which the thin film 102 is formed is a cubic (001) or pseudo-cubic (001) plane. In the thin film 102, the oxygen octahedron is rotated with respect to the crystal axis of the pseudo-cubic crystal of SrRuO3.

The invention discloses a GaN-based blue-green light LED epitaxial wafer based on a Zn-doped gradient composite buffer layer and a preparation method of the GaN-based blue-green light LED epitaxial wafer. The epitaxial wafer comprises a substrate, a zinc-doped gradient composite buffer layer and a gallium nitride-based epitaxial laminated structure, and the zinc element concentration is in gradient distribution along the growth direction, preferably, the zinc element concentration is gradually reduced from the side close to the substrate to the side far away from the substrate. And the buffer layer comprises at least two of a Zn3N2 layer, a constant component ZnGaN layer or a component gradient ZnGaN layer. During preparation, the buffer layer is grown at the temperature of 400-850 DEG C, concentration gradient is realized by adjusting the flow ratio of zinc-containing and gallium-containing precursors, and forced doping is realized by adopting a 10-50-time high-flow compensation strategy in a high-temperature interval. According to the invention, lattice constant soft landing is realized by supercell matching of Zn3N2 and GaN, and nitrogen vacancy point defects are passivated in situ by using Zn atoms. Experiments prove that the luminous efficiency of the chip can be improved by about 0.81%, the ESD (Electro-Static Discharge) 4000V yield is improved to more than 98.2%, and the crystal quality and the reliability of the device are obviously enhanced.

This invention discloses a photonic crystal structure with multiple types of topological edge states and its implementation method, belonging to the field of photonic crystal and topological photonics technology. The photonic crystal consists of a triangular lattice structure composed of multiple sets of lattice units with a lattice constant of . Each set of lattice units includes multiple sub-lattice units composed of yttrium iron garnet magneto-optical pillars and NdFeB permanent magnets at their upper and lower ends. The sub-lattice units are uniformly distributed in a polygonal pattern, with their circumferential spacing divided into two groups: one group shrinks inward along the center of the sub-lattice, and the other group expands outward along the center of the sub-lattice, forming two nested triangular lattice structures. This structure, through the coordinated design of magnetization direction and lattice structure symmetry, simultaneously breaks the time-space inversion symmetry, achieving for the first time the coexistence of chiral and antichiral topological edge states, and chiral and Gull-Hall topological edge states, on the same photonic crystal structure configuration.

The invention discloses a graphite material and a preparation method thereof, an electrochemical device and electronic equipment. The graphite material meets the following conditions: La is less than or equal to 72 nm, and Lc is less than or equal to 15 nm; wherein La is a lattice constant of a graphite crystal in the graphite material on a 110 plane, and Lc is a lattice constant of the graphite crystal in the graphite material on a 002 plane; f is greater than or equal to 15 mN, and F is particle crushing force. An electrochemical device (especially a lithium ion battery) containing the composite material can ensure excellent first effect and fast charge performance, and also has excellent self-discharge performance, capacity performance and cycle performance.

The application relates to a test method for the change rule of film mismatch stress, and belongs to the technical field of film stress testing. The method uses a standard sample with a known lattice constant, combines a diffraction principle to perform reverse calibration, obtains an accurate working distance on any device, and eliminates the dependence on fixed mechanical size. The method clearly adopts a calculation of an electron wavelength that is corrected by relativity, ensures that the calculation of the wavelength still maintains theoretical accuracy under high-voltage conditions, realizes accurate determination of the size and type of film stress, and makes the measurement results have reliable comparability and reproducibility between different laboratories or devices. The method changes the electron beam incidence angle by rotating a sample table, collects RHEED images of a substrate and a grown film, determines the greatest common divisor of the lattice constants of the substrate and the film at the interface, clearly determines the interface matching mode, corrects the actual lattice constant of the substrate under the growth temperature by considering the influence of a thermal expansion coefficient on the lattice constant, and calculates the actual mismatch degree after the thermal expansion correction.

The invention discloses an ultra-high quality factor quasi-continuous domain bound state realization method, and relates to the field of micro-nano photonics resonators, and the method comprises the steps: designing a symmetric medium nano column, and exciting an internal Mie mode and a Fabry-Perot mode through adjusting the geometric parameters of the symmetric medium nano column; coupling of the two modes is accurately regulated and controlled, so that far-field radiation destructive interference is achieved, and a high-Q-value quasi-continuous domain bound state is formed under the condition of no symmetry breaking; the nano-columns are arranged into a periodic array, lattice constants are optimized, and the quality factor is improved to an ultrahigh level by using resonance coupling and collective interference effect between adjacent nano-columns. Symmetrical breaking is not needed, and higher structural robustness and preparation tolerance are achieved.

This application provides an optimized epitaxial material growth method for edge-emitting lasers, comprising: obtaining a first substrate and pre-treating the surface of the first substrate; epitaxially growing a buffer layer structure on the first substrate, the buffer layer structure comprising at least two buffer layers with gradually changing lattice constants for lattice matching transition between the substrate and the target epitaxial layer; epitaxially growing a target epitaxial layer stack on the buffer layer structure; wherein, during the growth of the buffer layer structure and the target epitaxial layer stack, the growth state is monitored based on a real-time monitoring system, and the growth process parameters are dynamically adjusted according to the monitoring feedback. Through the synergistic effect of "structural design - real-time feedback - dynamic control", the crystal integrity, interface sharpness and compositional uniformity of the epitaxial material are fundamentally improved, thereby providing a core material basis for the fabrication of low-threshold, high-efficiency and high-reliability edge-emitting lasers.

The present invention relates to a core-shell nanocrystal having a discrete core-shell structure comprising a core and a single crystalline shell, wherein the core comprises CeO2 and an alpha-emitter or a mother radionuclide of an alpha-emitter; and the single crystalline shell comprises a shell compound having a cubic space group with a lattice constant of 4.6 Å to 6.3 Å. The present invention further relates to the use of the core-shell nanocrystals in targeted alpha-therapy and to a method for synthesizing the core-shell nanocrystals.

The present application relates to an epitaxial structure, a method for manufacturing the same, a light emitting chip and a display panel. The epitaxial structure comprises: a GaAs substrate; a buffer layer, an N-type (Al m Ga 1‑m ) 0.5 In 0.5 P confinement layer, an N-type waveguide layer, an active layer, a P-type waveguide layer, a P-type (Al n Ga 1‑n ) 0.5 In 0.5 P confinement layer, a transition layer and a P-type current spreading layer; wherein 0.8 m Ga 1‑m ) 0.5 In 0.5 The minimum value of the lattice constant of the P confinement layer is greater than the lattice constant of the N-type waveguide layer, and the maximum value is less than 5.666; 0.8 n Ga 1‑n ) 0.5 In 0.5 The minimum value of the lattice constant of the P confinement layer is greater than the lattice constant of the P-type waveguide layer, and the maximum value is less than 5.666. The present application can reduce the lattice mismatch of the red LED and improve the crystal quality.

The invention provides a sensitive-response graphene stress sensor and a preparation method thereof, and relates to the technical field of graphene stress sensors. The sensor comprises a flexible light-emitting layer and a photonic lattice gel layer connected with the flexible light-emitting layer, a photonic crystal with a periodic nanostructure is embedded in the photonic lattice gel layer; when the photonic lattice gel layer is stretched, the lattice constant of the photonic crystal of the periodic nanostructure in the photonic lattice gel layer is stretched, and the wavelength of reflected light moves towards the long wave direction; when the photonic lattice gel layer is compressed, the lattice constant is reduced, and the wavelength of the reflected light moves towards the short wave direction; the graphene heterojunction light sensor is connected with the photonic lattice gel layer, the flexible light-emitting layer serves as a light-emitting source, light emitted by the flexible light-emitting layer is transmitted to the graphene heterojunction light sensor through the photonic lattice gel layer, and the graphene heterojunction light sensor collects the intensity and spectrum of transmitted light. And analyzing the intensity of the transmitted light and the strain of the spectrum sensing effect on the graphene stress sensor with sensitive response.