Anisotropy Ratio Research Articles

High-Performance, Polarization-Sensitive, Long-Wave Infrared Photodetection via Photothermoelectric Effect with Asymmetric van der Waals Contacts.

Long-wavelength infrared (LWIR) photodetection is important for heat-seeking technologies, such as thermal imaging, all-weather surveillance, and missile guidance. Among various detection techniques, photothermoelectric (PTE) detectors are promising in that they can realize ultra-broadband photodetection at room temperature without an external power supply. However, their performance in terms of speed, responsivity, and noise level in the LWIR regime still needs further improvement. Here, we demonstrated a high-performance PTE photodetector based on low-symmetry palladium selenide (PdSe2) with asymmetric van der Waals contacts. The temperature gradient induced by asymmetric van der Waals contacts even under global illumination drives carrier diffusion to produce a photovoltage via the PTE effect. A responsivity of over 13 V/W, a response time of ∼50 μs, and a noise equivalent power of less than 7 nW/Hz1/2 are obtained in the 4.6-10.5 μm regime at room temperature. Furthermore, due to the anisotropic absorption of PdSe2, the detector exhibits a linear polarization angle sensitive response with an anisotropy ratio of 2.06 at 4.6 μm and 1.21 at 10.5 μm, respectively. Our proposed device architecture provides an alternative strategy to design high-performance photodetectors in the LWIR regime by utilizing van der Waals layered materials.

Anisotropy of the Proton Kinetic Energy as a Tool for Capturing Structural Transition in Water Confined in a Graphene Nanoslit Pore.

The proton dynamics of a 2D water monolayer confined inside a graphene slit pore is studied in Cartesian and molecular frames of reference using molecular dynamics simulations. The vibrational density of states of the proton was calculated versus temperature and was further used to deduce the mean kinetic energy of the hydrogen atoms, Ke(H), in both frames of reference. The directional components of Ke(H) are in good agreement with experimental observations for bulk as well as nanoconfined water. Nonetheless, while in the molecular frame of reference the effect of temperature on the anisotropy ratios of Ke(H) (the ratio between its directional components) are practically invariant between the 2D and 3D cases, those in the Cartesian frame of reference reveal a rather notable reduction across 200 K, indicating the occurrence of an order-disorder transition. This result is further supported by the calculated entropy and enthalpy of the confined water molecules. Overall, it is shown that Ke(H) anisotropy ratios may serve as a valuable order parameter for detecting structural transformations in hydrogen bonds containing molecular systems.

Effective anisotropic properties of fibre network sheets

The effective mechanical properties of plane fibre networks have been derived using discrete homogenization. The resulting equivalent continuum presents strong directional properties, with anisotropy ratios much larger than those that can be found in natural materials. The directionality of the response of the equivalent continuum increases with the slenderness of the fibres, leading to peculiar behaviours, like the formation of narrow bands where the strains present very large gradient. The results of the homogenization have been validated comparing the response of the continuum with the response of “discrete” models, for which each element is modelled as a slender beam, and boundary conditions are accounted for in an exact way.

Nanoscale-Thick Ni-Based Half-Heusler Alloys with Structural Ordering-Dependent Ultralow Magnetic Damping: Implications for Spintronic Applications

Atomic ordering and its consequence on the crystal structure are fundamental issues in the application of half-metallic Heusler alloys considered as a high spin-polarized electron source. NiMnSb is a promising half-metallic half-Heusler alloy for spintronic devices due to its low magnetic damping, non-centrosymmetric crystal structure, and rich anisotropies. Here, we report a high-quality half-metallic epitaxial nano-scale thick NiMnSb alloy film grown on a Cr/Ag-buffered MgO (001) single crystalline substrate. High temperature deposition is a crucial parameter for crystal growth and magneto-dynamic properties such as damping, anisotropy, magnetization, etc. After investigating the ferromagnetic resonance (FMR) spectroscopy using a time-resolved magneto-optical Kerr (TRMOKE) microscope and calculating the crystal structure using VESTA and the density of states from first-principles calculations, we discuss how the deposition temperature influences the crystal ordering, damping, and magnetization. Ultralow Gilbert damping with high anisotropic field and saturation magnetization were found for the highly ordered C1b structured nano-scale thick NiMnSb film deposited at 573 K. We also found quite nice agreement between theoretical and experimental data of crystal ordering and damping that explains how the ordering affects the magnetic parameter as well as sample quality. Furthermore, the negative anisotropic magnetoresistance ratio implies the robust bulk half-metallicity. Such unique combination of highly ordered half-metallic NiMnSb alloy in the nano-scale regime with ultralow damping can be regarded as an advantage for applications in spintronic devices.

Anisotropy characterization of the elasticity and energy flow of Longmaxi shale under uniaxial compression

The inherent anisotropy of shale makes it exhibit different mechanical properties when measured in different directions. Generally, the measurements of the anisotropic mechanical properties of shale are generally conducted on cylindrical samples, and the computation of elastic constants is usually an empirical approximation. To accurately estimate the elastic parameters of shale rocks, an iterative method for approaching the crack initiation stress threshold was proposed in this work. Several uniaxial compression experiments were performed on cuboid Longmaxi shale samples with different bedding plane orientations. With a newly presented method, the apparent elastic modulus and Poisson’s ratios and five elastic constants were simultaneously determined. By examining the volumetric strain reversal point, the crack damage stress was obtained for each sample. The results demonstrate that the elastic regime, which was the range in which the elastic parameters were determined, significantly varies with bedding plane orientation. A transverse anisotropy ratio of 1.28 between in-plane modulus E1 and out-of-plane modulus E3 was determined for Longmaxi shale. Additionally, with the obtained elastic parameters, the energy releasing and dissipating behaviors of the samples during uniaxial loading were quantitatively characterized. The energy dissipation was found to rapidly increase once the crack damage stress was reached. However, before rock failure occurred, the total dissipated energy in each sample was very limited, indicating that microcrack propagation and rock damage were quite limited before rock rupture and that the shale samples were essentially destroyed by rapid energy release.

A treatment protocol for controlling gas oil ratio in heterogeneous carbonate reservoirs by foam injection: Case study simulation

In this study, foam is selected to treat production wells of heterogeneous reservoirs that are suffering from high amounts of gas oil ratio (GOR). To this end, a numerical study is carried out by injecting foam through the perforations that produce high amounts of gas to block the gas path and allow much more oil to be simultaneously produced from the remaining perforations by applying a new technology in well completion. For this purpose, three heterogeneous synthetic base sectors are simulated in which large amounts of injected gas are produced from the upper, middle and lower perforations of the producing well, known as gas overriding, gas channeling-midriding and gas channeling-underriding, respectively. Since Kv/Kh is an important, decisive and effective parameter, different values of it have been considered for each of three base sector models including 0.001, 0.01, 0.1, 0.3, 0.5, 0.7, 0.9 and 1.0. Then, depending on the magnitude of Kv/Kh, the most optimal treatment method is sensitivity analyzed. In the following, foam injection parameters, e.g. surfactant concentration, depth of packer set, foam injection sequence and foam injection rate are sensitivity analyzed. Also, the phenomenon of gas cross-flow during the treatment process is investigated. The simulation results show that if after some time following well treatment, the GOR level increased, it is suggested to take a production test to determine what length of the production well below the packer produces lots of gas to set the packer at the lower depth and inject a larger volume of foam to block that gas path so that the GOR is reduced. The results also conclude that the magnitude of Kv/Kh on one hand and the location of gas entry to the production well on the other hand play a key role in the selection of the best treatment scenario in heterogeneous reservoirs. This has led to presenting a protocol for treatment of high GOR production wells in a wide range of reservoirs based on anisotropy ratios. Finally, in order to validate the protocol, a real specific sector of a heterogeneous carbonate reservoir located in the Middle East, in which the GOR level has increased, is simulated and treated. The results indicate that the protocol is efficient and causes a reduction in GOR by 60%. • A comprehensive treatment protocol for high GOR production wells is presented. • The effect of different anisotropy ratios is investigated. • A new method of foam injection/oil production is used at the simulation scale.

One Step Fabrication of Aligned Carbon Nanotube Sheet via FC‐CVD Technique

The rising need for lightweight and strong mechanical structures has contributed significantly towards the development of CNT macrostructures; however, the interplay of parameters and their discontinuous synthesis have obstructed their delivery to commercial level. Herein, floating catalyst chemical vapor deposition technique (FC‐CVD) has been employed for the fabrication of 90 cm long CNT sheet via continuous production of CNT aerogel. High degree of graphitization, thermal stability and purity have been indicated by Raman spectroscopy (IG/ID = 10.03), thermogravimetric analysis, and SEM studies. Continuous winding of CNT aerogel has increased the alignment into the sample which resulted into high electrical conductivity value of 21400 S/m. Furthermore, the alignment has been quantified by calculating optical anisotropic ratio via polarized Raman technique and conductivity anisotropic ratio κ‖ /κ⊥ which were calculated to be 4.63 and 3.4, respectively, and show reasonable agreement. These findings indicate that a well correlation of synthesis parameters results in highly aligned CNT sheet structure in a single step.

Laboratory study of fracture permeability of mineral-filled coal from Fanzhuang Block, southern Qinshui Basin, China

Coalbed methane (CBM) has achieved commercial production in China over the past decade. However, its single well production rate is relatively low. This is mainly due to the low coal permeability, which is a critical property for gas production. Fanzhuang block, southern Qinshui Basin, is a main CBM production area in China. The coals have mineral fillings in the cleat system and the mineral fillings have significant impact on coal permeability, thus the production rate. In this work, methane permeabilities on two selected samples from the Fanzhuang block were measured from high gas pressure to low gas pressure, simulating the gas production process. CT scans were performed on the two samples and two sets of fracture systems were observed. One set of fractures was filled with minerals, while another set of fractures was open. Therefore, the impact of minerals filling on permeability and fracture compressibility is complex. Moreover, the strong swelling strain anisotropy and low Poisson's ratio are also speculated to be closely related to the mineral fillings in the fracture system. • The permeability evolutions of mineral filled coal fracture samples are studied. • The measurement procedure has a significant impact on permeability results. • Mineral fillings in the facture have complex impact on coal permeability. • Swelling anisotropy and mechanical properties are also highly impacted by mineral fillings.

Influence of Anisotropy on Thermosolutal Convection in Porous Media with Magnetic Field Effect

In the present study, both anisotropy and magnetic field effects on bi-diffusive natural convection in a rectangular cavity filled with a porous medium saturated by a binary fluid are investigated analytically for fully developed flow regime. The cavity is heated isothermally by the sides and its horizontal walls are thermally insulated or conducted. The porous medium is anisotropic in permeability whose principal axes are oriented in a direction that is arbitrary to the gravity field. On the basis of the generalized Brinkman-extended Darcy model of newtonian fluids on steady flow through porous media, analytical expressions were obtained for the flow and thermal fields, the concentration of speaces, the average Nusselt and Sherwood numbers in terms of the Darcy number, the anisotropic permeability ratio, the orientation angle of the principal axes and the Hartmann number. The limiting case corresponding to pure porous media (<i>Da</i>→0) and pure fluid media (<i>Da</i>→∞) for the thermal conditions mentioned on the cavity completed these results in order to compare them to those obtained in the literature. It is found that, Nusselt and Sherwood numbers increase by increasing anisotropic parameters of the porous medium while increasing magnetic field magnitude greatly reduces the intensity of the flow and thus affects significantly heat and mass transfer.

Anisotropic Conductivity of Rat Head Phantom and its Influence on Electroencephalogram Source Localization

In this paper we deal with a simplified anisotropic rat head phantom development and the investigation of the influence of the anisotropic white matter on electroencephalogram source localization. The proposed phantom is based on the cubic cross cell composition combined with agar mixture to set desired electrical conductivity anisotropic ratio. For the fabrication of the phantom, the 3D printed technology is exploited. Starting from a real rat brain, we proposed a simplified brain model incorporating the actual dimensions, shape and conductivity parameters of both grey and white matter containing simultaneously relevant deep-brain electrical signal sources. Five testing dipoles were located in the areas corresponding to the active brain regions. A single dipole localization error was calculated by comparing an inverse solution with a dipole position obtained from a computer tomography image. Neglecting anisotropy had a rather weak effect on localization error of a single testing dipole in our model. The reliability map was computed and interpreted in terms of spatial similarity between distributed inverse solutions involving isotropic and anisotropic forward models. We found spatially specific error increases located close to the electrodes and in the vicinity of anisotropic compartment. Hence, areas to be most sensitive to neglecting anisotropy in our model were identified.

Prediction of the motor prognosis with diffusion tensor imaging in hemorrhagic stroke: a meta-analysis.

This paper investigates whether diffusion tensor imaging performed within 2 weeks of intracerebral hemorrhage onset could predict the motor outcome by categorizing previous diffusion tensor imaging studies based on the time-point of performing diffusion tensor imaging (<2 weeks and ≥2 weeks after intracerebral hemorrhage onset). A comprehensive database search on PubMed, Embase, Cochrane Library, and SCOPUS was conducted. The pooled estimate was acquired using correlation analysis between the diffusion tensor imaging parameters of fractional anisotropy and motor recovery based on the period of stroke onset. In the results, out of 511 retrieved articles, eight were finally included in the meta-analysis. In patients who underwent diffusion tensor imaging within 2 weeks of intracerebral hemorrhage onset, a random-effects model revealed that the ratio of fractional anisotropy is a significant predictor of motor recovery of the hemi-side extremity after intracerebral hemorrhage (p = 0.0015). In patients who underwent diffusion tensor imaging after 2 weeks of intracerebral hemorrhage onset, a fixed-effects model revealed that the ratio of fractional anisotropy was also a significant predictor of motor recovery of the hemi-side extremity after intracerebral hemorrhage (p < 0.0001). Our meta-analysis revealed that ratio of fractional anisotropy (rFa) calculated from diffusion tensor imaging (DTI) performed ≥2 weeks of intracerebral hemorrhage onset had a positive correlation with the motor outcomes after intracerebral hemorrhage (ICH). Also, although diffusion tensor imaging was performed <2 weeks after intracerebral hemorrhage onset, the ratio of fractional anisotropy calculated from diffusion tensor imaging helped predict the motor outcome. Further analyses, including a more significant number of studies focused on this topic, are warranted.

Shear–induced anisotropy in granular materials under various saturation states

This study presents a micromechanical study on the characteristics of shear-induced anisotropy in granular media under various saturation states. A series of unsaturated triaxial compression tests under the full range of degree of saturation are performed by using Discrete Element Method (DEM). The effect of the suctions on the characteristics of anisotropy is illustrated and discussed. Good agreements between anisotropy and stress ratio are observed for saturated and unsaturated states if skeleton contact stress is adopted. With the increase of the suctions, the weight of fabric tensor anisotropy decreases while the weight of anisotropy related to normal forces increases. The mechanical anisotropy plays a dominant role in providing shear resistance for the full saturation range.

Muscle Electrical Impedance Properties and Activation Alteration After Functional Electrical Stimulation-Assisted Cycling Training for Chronic Stroke Survivors: A Longitudinal Pilot Study

Electrical impedance myography (EIM) is a sensitive assessment for neuromuscular diseases to detect muscle inherent properties, whereas surface electromyography (sEMG) is a common technique for monitoring muscle activation. However, the application of EIM in detecting training effects on stroke survivors is relatively few. This study aimed to evaluate the muscle inherent properties and muscle activation alteration after functional electrical stimulation (FES)-assisted cycling training to chronic stroke survivors. Fifteen people with chronic stroke were recruited for 20 sessions of FES-assisted cycling training (40 min/session, 3–5 sessions/week). The periodically stimulated and assessed muscle groups were quadriceps (QC), tibialis anterior (TA), hamstrings (HS), and medial head of gastrocnemius (MG) on the paretic lower extremity. EIM parameters [resistance (R), reactance (X), phase angle (θ), and anisotropy ratio (AR)], clinical scales (Fugl-Meyer Lower Extremity (FMA-LE), Berg Balance Scale (BBS), and 6-min walking test (6MWT)] and sEMG parameters [including root-mean square (RMS) and co-contraction index (CI) value] were collected and computed before and after the training. Linear correlation analysis was conducted between EIM and clinical scales as well as between sEMG and clinical scales. The results showed that motor function of the lower extremity, balance, and walking performance of subjects improved after the training. After training, θ value of TA (P = 0.014) and MG (P = 0.017) significantly increased, and AR of X (P = 0.004) value and AR of θ value (P = 0.041) significantly increased on TA. The RMS value of TA decreased (P = 0.022) and a significant reduction of CI was revealed on TA/MG muscle pair (P < 0.001). Significant correlation was found between EIM and clinical assessments (AR of X value of TA and FMA-LE: r = 0.54, P = 0.046; X value of TA and BBS score: 0.628, P = 0.016), and between sEMG and clinical scores (RMS of TA and BBS score: r = −0.582, P = 0.029). This study demonstrated that FES-assisted cycling training improved lower limb function by developing coordinated muscle activation and facilitating an orderly myofiber arrangement. The current study also indicated that EIM can jointly evaluate lower extremity function alteration with sEMG after rehabilitation training.Clinical Trail Registration: The study was registered on the Clinical Trial Registry (trial registration number: NCT 03208439, https://clinicaltrials.gov/ct2/show/NCT03208439).

A Polarization-Sensitive Self-Powered Photodetector Based on a p-WSe2/TaIrTe4/n-MoS2 van der Waals Heterojunction.

Polarization-sensitive photodetection is highly appealing considering its great important applications. However, the inherent in-plane symmetry of a material and the single structure of a detector hinder the further development of polarization detectors with high anisotropic ratios. Herein, we design a p-WSe2/TaIrTe4/n-MoS2 (p-Ta-n) heterojunction. As a type-II Weyl semimetal, TaIrTe4 with an orthorhombic structure has strong in-plane asymmetry, which is confirmed by angle-resolved polarized Raman spectroscopy and second-harmonic generation. Due to the specific structure of the p-Ta-n junction with two vertical built-in electric fields, the device obtains a broadband self-powered photodetection ranging from visible (405 nm) to telecommunication wavelength (1550 nm) regions. Further, an optimized device containing 50-70 nm-thick layered TaIrTe4 has been realized. What is more, high-resolution imaging of "T" based on the device with clear borders illustrates excellent stability of the device. Significantly, the photocurrent anisotropic ratio of the p-Ta-n detector can reach 9.1 under 635 nm light, which is more than eight times that of the best known TaIrTe4-based photodetector reported before. This p-Ta-n junction containing a type-II Weyl fermion semimetal can provide an effective approach toward highly polarization-sensitive and high-performance integrated broadband photodetectors.

Control of Surface Wrinkling through Compliant Nanostructured Interfaces

AbstractSurface wrinkling occurs due to the mechanical instability induced by the stiffness mismatch between a soft substrate and a stiff film. In a two‐layer system comprised of a thick compliant substrate and a thin stiff film, the wrinkle pattern, as described by the wrinkle wavelength, amplitude, and orientation, is limited by the material properties and thickness of the two layers. In this work, an interface layer of nanostructures fabricated by glancing angle deposition (GLAD) is introduced to modify the surface wrinkling of polydimethylsiloxane due to a Cu film, thus enabling improved control of wrinkling in an otherwise constrained material system. Isotropic (nanospring) and orthotropic (nanochevron) Cu interfaces are GLAD‐deposited with different geometric parameters to control the in‐plane stiffness of the interface. The isotropic nanospring films provide a novel means to control the physical length scale of wrinkle patterns, namely, both the wavelength and the amplitude of surface wrinkles, while maintaining the amplitude‐to‐wavelength aspect ratio. The anisotropic nanochevron films result in anisotropy ratio of ≈10 which provides a unique means to modify the wrinkle direction independently of the direction of the applied load. The prediction by the experimentally calibrated analytical model is shown to be in good agreement with the experiment.

Strong In-Plane Anisotropic SiP2 as a IV-V 2D Semiconductor for Polarized Photodetection.

In-plane anisotropic two-dimensional (2D) materials, emerging as an intriguing type of 2D family, provide an ideal platform for designing and fabrication of optoelectronic devices. Exploring air-stable and strong in-plane anisotropic 2D materials is still challenging and promising for polarized photodetection. Herein, SiP2, a 2D IV-V semiconductor, is successfully prepared and introduced into an in-plane anisotropic 2D family. The basic characterizations combined with theoretical calculations reveal 2D SiP2 to exhibit an intrinsically low-symmetry structure, the in-plane anisotropy of phonon vibrations, and an anisotropically dispersed band structure. Moreover, the photodetector based on 2D SiP2 exhibits high performance with a high detectivity of 1012 Jones, a large light on/off ratio of 103, a low dark current of 10-13 A, and a fast response speed of 3 ms. Furthermore, 2D SiP2 demonstrates a high anisotropic photodetection with an anisotropic ratio up to 2. In addition, the polarization-sensitive photodetector presents a dichroic ratio of 1.6 due to the intrinsic linear dichroism. These good characteristics make 2D SiP2 a promising candidate as an in-plane anisotropic semiconductor for high-sensitivity and polarized optoelectronic applications.

Dispersion in doublet-type flows through highly anisotropic porous formations

Steady doublet-type flow takes place in a porous formation, where the log-transform $Y = \ln K$ of the spatially variable hydraulic conductivity $K$ is regarded as a stationary random field of two-point autocorrelation $\rho _Y$ . A passive solute is injected at the source in the porous formation and we aim to quantify the resulting dispersion process between the two lines by means of spatial moments. The latter depend on the distance $\ell$ between the lines, the variance $\sigma ^2_Y$ of $Y$ and the (anisotropy) ratio $\lambda$ between the vertical and the horizontal integral scales of $Y$ . A simple (analytical) solution to this difficult problem is obtained by adopting a few simplifying assumptions: (i) a perturbative solution, which regards $\sigma ^2_Y$ as a small parameter, of the velocity field is sought; (ii) pore-scale dispersion is neglected; and (iii) we deal with a highly anisotropic formation ( $\lambda \lesssim 0.1$ ). We focus on the longitudinal spatial moment, as it is of most importance for the dispersion mechanism. A general expression is derived in terms of a single quadrature, which can be straightforwardly carried out once the shape of $\rho _Y$ is specified. Results permit one to grasp the main features of the dispersion processes as well as to assess the difference with similar mechanisms observed in other non-uniform flows. In particular, the dispersion in a doublet-type flow is observed to be larger than that generated by a single line. This effect is explained by noting that the advective velocity in a doublet, unlike that in source/line flows, is rapidly increasing in the far field owing to the presence there of the singularity. From the standpoint of the applications, it is shown that the solution pertaining to $\lambda \to 0$ (stratified formation) provides an upper bound for the dispersion mechanism. Such a bound can be used as a conservative limit when, in a remediation procedure, one has to select the strength as well as the distance $\ell$ of the doublet. Finally, the present study lends itself as a valuable tool for aquifer tests and to validate more involved numerical codes accounting for complex boundary conditions.

Sequential Diffusion Tensor Imaging and Magnetic Resonance Spectroscopy in Patients Undergoing Reirradiation for Progressive Diffuse Intrinsic Pontine Glioma

PurposeDiffusion tensor imaging for evaluation of white matter tracts is used with magnetic resonance spectroscopy (MRS) to improve management of diffuse intrinsic pontine glioma (DIPG). Changes in the apparent diffusion coefficient (ADC), fractional anisotropy (FA), and tumor metabolite ratios have been reported after initial radiation for DIPG, but these markers have not been studied sequentially in patients undergoing reirradiation for progressive DIPG. Here, we report a case series of 4 patients who received reirradiation for progressive DIPG on a prospective clinical trial in which we evaluated quantitative changes in FA, ADC, and tumor metabolites and qualitative changes in white matter tracts. Methods and MaterialsThe median reirradiation dose was 25.2 Gy (24-30.8 Gy). Fiber tracking was performed using standard tractography analysis. The FA and ADC values for the corticospinal and medial lemniscus tracts were calculated before and after reirradiation. Multivoxel MRS was performed. Findings were correlated with clinical features and conventional MRI of tumors. ResultsAll patients had an initial response to reirradiation as shown by a decrease in tumor size. In general, FA increased with disease response and decreased with progression, whereas ADC decreased with disease response and increased with progression. At second progression, the FA fold change relative to values during disease response decreased in both patients with available imaging at second progression. Visualization of tracts demonstrated robust reconstitution of previously disrupted paths during tumor response; conversely, there was increased fiber tract disruption and infiltration during tumor progression. The MRS analysis revealed a decrease in choline:creatinine and choline:N-acetylaspartate ratios during tumor response and increase during progression. ConclusionsDistinct changes in white matter tracts and tumor metabolism were observed in patients with DIPG undergoing reirradiation on a prospective clinical trial. Changes related to tumor response and progression were observed after 24 to 30.8 Gy reirradiation.

Integrated polarization-sensitive amplification system for digital information transmission

Polarized light can provide significant information about objects, and can be used as information carrier in communication systems through artificial modulation. However, traditional polarized light detection systems integrate polarizers and various functional circuits in addition to detectors, and are supplemented by complex encoding and decoding algorithms. Although the in-plane anisotropy of low-dimensional materials can be utilized to manufacture polarization-sensitive photodetectors without polarizers, the low anisotropic photocurrent ratio makes it impossible to realize digital output of polarized information. In this study, we propose an integrated polarization-sensitive amplification system by introducing a nanowire polarized photodetector and organic semiconductor transistors, which can boost the polarization sensitivity from 1.24 to 375. Especially, integrated systems are universal in that the systems can increase the anisotropic photocurrent ratio of any low-dimensional material corresponding to the polarized light. Consequently, a simple digital polarized light communication system can be realized based on this integrated system, which achieves certain information disguising and confidentiality effects.

Angular dependence of the critical current density in FeSe0.5Te0.5 thin films on metal substrates

Biaxially textured FeSe0.5Te0.5 (FST) thin films were fabricated on ion-beam assisted-deposition LaMnO3 (LMO) buffered metal substrate with additional CeO2 as a buffer layer. Profiting from the implementation of CeO2 layers, the resultant FST films show a small out-of-plane misalignment of about 2.04° and an in-plane misalignment around 4.02°. In addition, the films have a high superconducting transition temperature (T c) ∼ 17 K and a comparatively high critical current density (J c) of 0.78 MA cm−2 in self-field at 4.2 K. On the other hand, a high J c peak for H//c above H//ab at temperatures below 10 K was observed, which results from grain boundaries along the c-axis. In addition, J c peaks for H//ab emerge above 10 K and become more pronounced than those for H//c at 12 K, indicating both a temperature- and field-dependent pinning mechanism. Moreover, J c(θ) data except for in the vicinity of H//ab and H//c can be successfully scaled using the anisotropic Ginzburg–Landau approach with an appropriate J c anisotropy ratio of γJ c ∼ 1.5, implying the presence of both ab-plane and c-axis correlated flux pinning centers in FST films.