Anisotropy Ratio Research Articles

Anomalous Ultra‐Broadband Photoresponse Based on PdSe2 with Asymmetric Contact

AbstractAnomalous photoresponse with negative photoconductance (NPC) is rarely observed which is quite different from the common semiconductor with positive photoconductance (PPC) as the light can induce additional carriers. NPC effect is not widely studied because the performance of the NPC is limited and the device fabrication is uncontrollable. Here, a controllable way is reported to fabricate an anomalous photoresponse device through asymmetric metal contact with the PdSe2. A mirror electrode‐enhanced vertical asymmetric contact (VAC) PdSe2 device is designed. The VAC PdSe2 device demonstrated the NPC effect in an ultra‐broadband spectral range from 637 nm to the long‐wave infrared (LWIR) 10.6 µm. Notably, the device exhibits excellent uncooled mid‐wave infrared (MWIR) and LWIR detection ability with a high photoresponsivity (R) of 128.4 AW−1 and 38.2 AW−1, respectively. Furthermore, the lateral asymmetric contact (LAC) PdSe2 device is also investigated. The LAC PdSe2 device demonstrated competitive performance including high photovoltaic responsivity up to 0.22 AW−1 and external quantum efficiency (EQE) of 67.5%, fast photoresponse speed with rise time τr = 28.7 µs and decay time τd = 31.2 µs, and anisotropic dichroic ratio (γ) of ≈1.15. The results open a new platform for studying anomalous photoresponse with high performance in uncooled LWIR photodetection.

Cross-sectional optimisation of I-shape pultruded FRP beams using search-adaptive micro-population genetic algorithm

Despite the growing utilisation of pultruded fibre-reinforced polymers (PFRP) profiles in infrastructure applications, there is still a scarcity of design tools with a feasible computational cost. Such shortage deprives these profiles of competing with economic cost and optimised performance against other construction materials. This research investigated the numerical optimisation of cross-sectional geometry and anisotropy ratio of I-shape PFRP beams for the design against local buckling of flange under bending and web under transverse compression. A new search-adaptive micro-population genetic algorithm (SA-µP GA) tool was proposed to achieve accurate results with low computational cost. This tool was verified and compared with other GA codes from the literature. The artificial neural networks (ANNs) machine learning tool was used to maximise the use of data and generate practical and economic design charts considering the varying interactions between the design parameters. This optimisation approach represents an efficient design tool to achieve the design requirements of stability, strength, and serviceability (stiffness) limits with minimum cost and optimal structural performance. The optimisation approach was addressed using four case studies from the literature.

Remodeling and Characterization Analysis of Corticospinal Tract in Patients with Intracerebral Hemorrhage in the Basal Ganglia.

To investigate corticospinal tract (CST) injury and remodeling in patients with basal ganglia intracerebral hemorrhage (ICH) and explore the characterization capabilities of the corresponding parameters. In this prospective study, baseline, scale, and diffusion-weighted imaging (DWI) data were collected from patient cohorts. Participants were stratified into favorable (0-3 points) and unfavorable (4-6 points) prognosis groups, based on Modified Rankin Scale (mRS) after 3-6months. The analysis of DWI data was conducted employing FSL and DSI Studio software to compare CST injury between the prognosis groups and CST remodeling features. A partial correlation model was deployed to elucidate the characterization capability of CST-related parameters. Additionally, logistic regression analysis was applied to identify factors significantly influencing prognosis. A total of 65 patients were enrolled with a mean age of 53.52years and a median hematoma volume of 23.60ml. The 44 patients were classified within the favorable prognosis group, demonstrating a statistically significant difference in their lower mean age (P = 0.002). Additionally, 10 patients underwent DWI review with a mean age of 50.30years and a median hematoma volume of 18.56ml. The investigation uncovered evidence of CST damage versus remodeling at the group level, respectively, with statistical significance (FDR-corrected P < 0.05, 10,000 permutations). The fractional anisotropy (FA) ratio in the internal capsule region exhibited moderate correlation with motor function (r = 0.507, P < 0.001) and the 3- to 6-month mRS scores (r = - 0.318, P < 0.013). Furthermore, binary logistic regression analysis identified the FA rate in the internal capsule as a significant influencing factor of prognosis (odds ratio = 1.027, 95% confidence interval = 1.003-1.052, P = 0.025). Basal ganglia ICH can coincide with injury to the CST, which could undergo repair over time. Additionally, the FA ratio of the internal capsule is a potential biomarker to characterize residual motor function and provide prognostic information.

PdSe2/NbSe2 Heterojunction Photodetector with Broadband Detection and Polarization Sensitivity.

Polarized photodetectors based on anisotropic two-dimensional (2D) materials display great potential applications in communications and optoelectronics. However, the existence of high dark current, low anisotropic ratio, and response speed limits their development. In this paper, a broadband polarization angle-dependent photodetector based on the PdSe2/NbSe2 van der Waals (vdW) heterojunction has been constructed. Characterization results show that the PdSe2/NbSe2 heterojunction photodetector can suppress the dark current effectively (NbSe2 ∼4 orders of magnitude and PdSe2 ∼1 order of magnitude compared with individual material). Meanwhile, the device exhibits a broadband detection capability ranging from 405 to 980 nm. The device shows a superior responsivity of 27 mA/W, a considerable detectivity of 9.8 × 107 Jones, a large external quantum efficiency of 528%, and an ultrafast rise/decay time of 1.6/1.9 μs at 1 V bias under 638 nm laser wavelength. The photodetector also achieves a high polarization-sensitive anisotropic ratio of ∼2.62 under 638 nm laser irradiation. In addition, the heterojunction device shows outstanding polarization imaging capabilities, which can be used as the image sensor. This work proposed a PdSe2/NbSe2 vdW heterojunction device with low dark current, broadband polarized detection, and polarized visual imaging, which will promote the development and practicality of polarization-sensitive photodetectors.

Multifunctional Native Defects Boosting the Thermoelectric Transport in Few‐Layer PdPS

AbstractAs a unique Cairo pentagonal 2D material, palladium phosphide sulfide (PdPS) has garnered immense interests due to its excellent optoelectronic properties, anisotropic electronic transport behavior, and good air‐stability. In addition, its puckered pentagon structure renders an ultralow thermal conductivity, making it a promising candidate for thermoelectrics applications. However, its thermoelectric transport has not been studied until now due to challenges in obtaining the atomic thin PdPS flake and further measurement. In this work, the thermoelectric performance of 2D PdPS is investigated. It is found that thermoelectric property of PdPS can be effectively manipulated via the delicate annealing treatment, which effectively regulate the defect concentrations. Remarkably, beyond regulating carrier concentrations and shifting the Fermi level closer to the conduction band, these defects also produce a large number of defect states. Consequently, ultra‐high power factor of 0.648 mW m−1 K−2 at room temperature is achieved, outperfoming other 2D materials reported to date. Furthermore, the anisotropic electronic transport properties of few‐layer PdPS are further studied and an extremely high electron anisotropic ratio of 47.37 are obtained at 20 K. The findings provide a new pathway for the development of nanoelectronic devices based on emerging 2D materials with high electronic anisotropy and thermoelectric performance.

Giant anisotropic piezoresponse of layered ZrSe3.

We investigated the effect of uniaxial strain on the electrical properties of few-layer ZrSe3 devices under compressive and tensile strains applied up to ±0.62% along different crystal directions. We observed that the piezoresponse, the change in resistance upon application of strain, of ZrSe3 strongly depends on both the direction in which electrical transport occurs and the direction in which uniaxial strain is applied. Notably, a remarkably high anisotropy in the gauge factor for a device with the transport occurring along the b-axis of ZrSe3 with GF = 68 when the strain is applied along the b-axis was obtained, and GF = 4 was achieved when strain is applied along the a-axis. This leads to an anisotropy ratio of almost 90%. Devices whose transport occurs along the a-axis, however, show much lower anisotropy in gauge factors when strain is applied along different directions, leading to an anisotropy ratio of 50%. Furthermore, ab initio calculations of strain dependent change in resistance showed the same trends of the anisotropy ratio as obtained from experimental results for both electrical transport and strain application directions, which were correlated with bandgap changes and different orbital contributions.

Range and accuracy of in-plane anisotropic thermal conductivity measurement using the laser-based Ångstrom method.

High heat fluxes in electronic devices must be effectively dissipated to prevent local hotspots, which are critical for long-term device reliability. In particular, advanced semiconductor packaging trends toward thin form factor products increase the need for understanding and improving in-plane conduction heat spreading in anisotropic materials. The 2D laser-based Ångstrom method, an extension of traditional Ångstrom and lock-in thermography techniques, measures in-plane thermal properties of anisotropic sheet-like materials. This method uses non-contact infrared temperature mapping to measure the thermal response to periodic laser heating at the center of a suspended sample. The spatiotemporal temperature data are analyzed via an inverse fitting algorithm to extract thermal conductivities in the in-plane orthotropic directions that best adhere to the governing heat conduction equation. Using this algorithm, we present an approach to simultaneously fit data across multiple heating frequencies, which improves measurement sensitivity because the thermal penetration depth varies with frequency. The accuracy of this technique is assessed by tuning experimental parameters such as sample dimensions and heating frequency. A standardized workflow is proposed for measuring unknown materials and for processing the data, including filtering out regions influenced by laser absorption and heat sink boundary effects. Numerical simulations validate the method across a wide range of thermal conductivities (0.1-1000W m-1 K-1) and material thicknesses (0.1-10mm), with accuracy demonstrated for anisotropy ratios up to 1000:1. Experimental measurements on isotropic and anisotropic materials agree well with the benchmark values. Ultimately, standardization of this technique supports the development of engineered anisotropic heat-spreading materials for thermal management and packaging applications.

Chemical Vapor Deposition Growth of Ternary Cu3PS4 Nanowires for Polarization‐Sensitive Photodetection

AbstractLow‐dimensional ternary materials with low‐symmetry structure have emerged as promising candidates for constructing polarization‐sensitive photodetectors. However, the photodetection applications of ternary materials remain challenging due to the limited varieties and the uncontrollable preparation. Herein, ternary Cu3PS4 nanowires with tunable thickness are successfully synthesized via chemical vapor deposition method. The grown Cu3PS4 nanowires present excellent structural anisotropy and strong in‐plane second‐order nonlinear optical anisotropy, as evidenced by angle‐resolved polarized Raman spectra and second harmonic generation measurements. Impressively, Cu3PS4‐based photodetector demonstrates a responsivity of 8.8 mAW−1, detectivity of 5.01 × 109 Jones, and photoresponse speeds with rise (decay) time of 1.5 (3.5) ms. Interestingly, the photodetector achieves polarization‐sensitivity photoresponse with an anisotropic ratio of 1.3 at 520 nm based on its inherent structural anisotropy and geometrical shapes. This work broadens the scope of synthesis strategy for various low‐dimensional ternary metal chalcohalide semiconductors and provides great opportunities for designing high‐performance and multifunctional optoelectronic devices.

Orientation-Related Giant Photothermoelectric Energy Conversion in Quasi-One-Dimensional van der Waals TaSe3 Crystals.

Featuring the capabilities of self-power, low dark current, and broadband response, photothermoelectric (PTE) detection demonstrates great potential for application in the military and civilian fields. The development of materials with an intrinsically high efficiency for PTE energy conversion and the in-depth study of its thermoelectric properties on the device performance are of great significance. Here, we reported a quasi-one-dimensional (quasi-1D) van der Waals (vdW) TaSe3 crystal as a promising material candidate for PTE detection. Benefiting from the 1D confined effect for photon and electron transport, the TaSe3 nanoribbon crystallized along the atomic chain direction demonstrates a size-dependent thermal conductivity and Seebeck coefficient. With the nanoribbon width downscaled from 5.7 μm to 200 nm, the resulting PTE detector reveals a pronouncedly enhanced photoresponsivity by more than 1 order of magnitude, demonstrating an extremely high value of 33 V/W among the best state-of-the-art PTE devices. More importantly, the anisotropic electrical, thermal, and thermoelectric properties in the TaSe3 crystal contribute to the orientation-related PTE energy conversion, yielding an anisotropic ratio of photoresponsivity as large as 2.5 under 532 nm light illumination. Our study provides experimental evidence of orientation-related giant PTE photodetection in the quasi-1D vdW TaSe3 crystal, which provides possibilities for the development of future optoelectronic devices.

Ambient-pressure anisotropic single-gap superconductivity in La-trapped B26 cages with superior hardness

Abstract Recently, the breakthrough high-pressure synthesis of the $sp^3$-bonded clathrate-like $R$-3$m$-LaB$_8$ featuring La-trapped B$_{26}$ cages was achieved. Although the superconducting critical temperature ($T_c$) and Vickers hardness ($H_v$) for LaB$_8$ were estimated, the anisotropic superconductivity and the superconducting gaps nature remain unclear. Meanwhile, the stability of pure B$_{26}$ cages under ambient conditions also piqued our interest in exploring the hardness of B$_{26}$ and the role of La atoms in hardness of LaB$_8$. By resolving the Allen-Dynes modified McMillan equation and the anisotropic Eliashberg equations, it is revealed that LaB$_8$ exhibits anisotropic single-gap superconductivity with $T_c$ of 19.0 $\sim$ 26.5 K, and the anisotropic ratio of the superconducting gap reaches up to 48.50% at 5 K. Most significantly, our work fundamentally validated the coupling of B-2$p$ orbitals with the optical double-degenerate $E_g$ phonon modes and $A_g$ phonon mode from a novel perspective. The $H_v$ of B$_{26}$ cages was determined to be 18.6 GPa, which is lower than that of La-trapped B$_{26}$ ones (i.e., LaB$_8$), indicating that the element La act as an enhancer of hardness for LaB$_8$.

A Room-Temperature Terahertz Photodetector Imaging with High Stability and Polarization-Sensitive Based on Perovskite/Metasurface.

Terahertz (THz) polarization detection facilitates the capture of multidimensional data, including intensity, phase, and polarization state, with broad applicability in high-resolution imaging, communication, and remote sensing. However, conventional semiconductor materials are limited by energy band limitations, rendering them unsuitable for THz detection. Overcoming this challenge, the realization of high-stability, room-temperature polarization-sensitive THz photodetectors (PDs) leveraging the thermoelectric effect of Cs0.05(FA0.85MA0.15)0.95Pb(I0.85Br0.15)3 (CsFAMA)/metasurfaces is presented. Two different structures of (T-shaped and I-shaped) THz PDs are constructed. The incorporation of perovskite/metasurfaces forms enhanced local field thermoelectric effect and polarization response. Owning to THz surface plasmon polariton (SPP) resonance effect and more boundary effect, the I-shaped PDs exhibit superior performance, achieving a response of up to 94V/W, with a response time of 138 µs, a low noise-equivalent power of 5.03 pW/Hz1/2 and an anisotropy ratio of 1.38 under 0.1THz laser irradiation. Furthermore, the PD's stability is verified with the anisotropy ratio decreased by only 2% and polarization imaging results after 240 days of storage in air condition. This research introduces a method for achieving high-performance, stable THz polarization detection technology, with significant potential for advancements in materials science, communication technology, and medical imaging.

Parametric Analysis for 3D Modeling of Consolidation-Induced Solute Transport Using OpenFOAM

Most previous investigations for consolidation-induced solute transport models have been limited to one-dimensional studies in unsaturated porous media and lack systematic parameter sensitivity analysis. This study addresses these gaps by analyzing the effects of hydraulic conductivity (K), shear modulus (G), saturation (Sr), Poisson’s ratio (ν), partitioning coefficient (Kd), and anisotropy ratio (KxKz and KyKz) on pore water pressure, soil deformation, and solute transport. The findings reveal that higher Kd values significantly hinder solute migration through enhanced adsorption and reduced vertical transport to deeper layers, while increasing anisotropy ratios primarily enhance horizontal migration, with their effects diminishing beyond a threshold. Additionally, a higher K accelerates pressure dissipation and solute movement, while a lower G increases soil deformation and speeds up solute migration. Saturation has a minor effect on solute concentration, with slight increases under higher Sr. The Poisson ratio significantly impacts the transport of the solute, with smaller ν accelerating and larger ν slowing migration. These insights offer valuable theoretical support for optimizing models in unsaturated porous media.

Strain-Mediated Second Harmonic Generation Enhancement of Bimetallic Metal-Organic Frameworks.

Triggered by the demand of developing practical metal-organic framework (MOF) based nonlinear optical (NLO) devices, there is a surge of research interest in the regulation of NLO properties of MOFs. Strain engineering provides a new opportunity to regulate the optoelectronic properties of materials and device performance at the interface. Here we introduce the induction of the strain field in structures by constructing bimetallic Zn/Cu-MOFs. The NLO response of MOF1-9 with different metal element ratios was characterized in the near-infrared window. Surprisingly, MOF3 exhibited a giant second harmonic generation (SHG) enhancement compared with that of pristine Zn- and Cu-MOF. The determined second-order nonlinear susceptibility of MOF3 (∼19.86 p mV-1) is one order of magnitude larger than that of pristine Zn-MOF (1.65 p mV-1) and Cu-MOF (3.88 p mV-1) and much higher than the commonly used NLO crystals. Moreover, the anisotropy ratios of MOF1-9 can be harnessed in a wide range (∼4.7-118.8). The anisotropy ratio of MOF4 (∼118.8) is much higher than that of the most excellent 2D material to date, to our best knowledge. A first-order perturbation of second-order polarization based on point group description was introduced to explore the regulation mechanism of the NLO response under the strain field of MOFs.

Effects of Anisotropic Microstructure and Load Ratio on Fatigue Crack Propagation Rate in Additively Manufactured Ti-6Al-4V Alloy

Additive manufacturing (AM) refers to advanced technologies for building 3D objects by adding material layer upon layer using either electron beam melting (EBM) or selective laser melting. AM allows us to produce lighter and more complex parts. However, various defects are created during the AM process, which severely affect fatigue behavior. In the current research, the effects of the anisotropic microstructure in the in-plane and out-of-plane orientations and defects on the fatigue crack propagation rate (FCPR) and crack path were studied. A resonance machine was used to determine the fatigue crack propagation rate (da/dN vs. ΔK) from the near-threshold up to the final fracture, accompanied by in situ Acoustic Emission (AE) monitoring. Micro-Computerized Tomography (µCT) enabled us to characterize surface and microstructural defects. Metallography was used to determine the microstructure vs. orientations and fractography to classify the fatigue fracture propagation modes. Calculations of the local stress distribution were performed to determine the interactions of the cracks with the defects. In the out-of-plane direction, the material exhibited high fatigue fracture toughness accompanied by a slightly lower fatigue crack propagation rate as compared to in-plane orientations. The near-threshold stress intensity factor was slightly higher in the out-of-plane orientation as compared to that in the in-plane one, accompanied by a lower exponent of the Paris law regime. The threshold decreased with an increasing load ratio as expected for both orientations. The crack propagation direction that crosses the elongated grains plays an important role in increasing fatigue resistance in the out-of-plane direction. In the in-plane directions, the crack propagates parallel to the grain boundary, interacts with more defects and exhibits more brittle striations on the fracture surface, resulting in lower fatigue resistance.

Impact of Anisotropic Permeability on Micropolar Fluid Dynamics and Heat Transfer in Porous Channels

The current study explores the fluid dynamics and heat transfer characteristics of micropolar fluids within a channel filled with anisotropic porous media. The governing equations for the fluid flow, microrotation, and temperature profiles are numerically solved using Spectral Quasi-Linearization Method (SQLM). The research examines the influence of various key parameters such as the anisotropic permeability ratio, anisotropic angle, Darcy number, Reynolds number, Brinkman number, Prandtl number, and coupling number. Key findings indicate that the anisotropic permeability ratio and anisotropic angle significantly affect fluid flow and heat distribution, with increased anisotropy leading to enhanced microrotation and temperature, albeit with reduced velocity at the channel center. Higher Darcy numbers result in less restricted flow, increasing velocity and reducing microrotation effects, while increasing the coupling number contributes to a more uniform temperature profile. These results provide significant insights into the optimization of heat transfer and flow control in engineering applications that involve micropolar fluids in porous media.

A Biomagnetic Couple Stress Fluid Flow in an Anisotropic Porous Channel with Stretching Walls

The present study investigates the dynamics of a biomagnetic couple stress fluid within an anisotropic porous channel where the channel walls are stretchable. This study examines the flow behavior under the influence of an external magnetic field generated by a magnetic dipole. Appropriate dimensionless parameters are introduced to simplify the equations of the problem. A suitable numerical approach based on the Spectral Quasi-Linearization Method is utilized to obtain a solution to the problem. In this work, influence of several important parameters like the anisotropic permeability ratio, couple stress parameter, anisotropic angle, Darcy number, ferromagnetic interaction parameter, Reynolds number, and Prandtl number are examined. The results indicate that ferromagnetic interaction parameter and couple stress parameter significantly impact heat transfer and fluid flow. Permeability ratio and angle also affect the flow dynamics. Furthermore, the coefficient of skin friction and rate of heat transfer were examined, varying the couple stress and ferromagnetic interaction parameters. The findings demonstrate that an existence of magnetic dipole and anisotropic permeability significantly influences the flow and thermal properties of ferrofluids, providing valuable insights for optimizing heat transfer and controlling fluid flow in diverse engineering and medical applications.

Analysis of electroosmotic flow in a symmetric wavy channel containing anisotropic porous material with varying zeta potential

The present study examines an asymptotic analysis of electroosmotic flow phenomena bounded by the symmetrical wavy channel containing an anisotropic porous material under the variable pressure gradient and zeta potential. The incorporation of anisotropic porous material introduces additional complexities to the flow behavior. Electric potential is regulated by the non-linear Poisson–Boltzmann equation, which is linearized by the Debye–Hückel linearization process, and flow velocity inside the porous channel is governed by the Brinkman equation. The aspect ratio of the channel is considered to be significantly small, i.e., (δ2≪1). Obtaining analytical solutions to these non-linear coupled equations is a formidable challenge. To address this challenge, the equations are tackled by employing an asymptotic series expansion with respect to a small parameter, specifically the ratio of the channel thickness, where δ2≪1. The graphical analysis based on the derived expressions for flow quantities—such as fluid velocity, flow rate, flow resistance, wall shear stress, and pressure gradient along the wall—demonstrates the considerable impact of various governing parameters. These parameters, including the Debye–Hückel parameter, anisotropic ratio, slip length, and fluctuation amplitude, play a crucial role in influencing the behavior of these flow characteristics, highlighting their importance in determining the system's overall flow dynamics. The results demonstrate that an increment in the anisotropic ratio corresponds to an enhancement in fluid velocity and augmented flow rate. This relationship stems from the observed phenomenon wherein an enhancement in the anisotropic ratio leads to an augmentation in the permeability along the x-direction, thereby leading to an elevation in velocity and subsequently enhancing the flow rate. The study also examines the impact of flow reversal at the crests of the wavy channel resulting from the anisotropic ratio. The findings from our study have confirmed the axial fluid velocity in a purely pressure-driven flow system, where electroosmotic effects are not present. These results enhance our understanding of how anisotropic permeability affects fluid flow in microfluidic systems, especially when electrokinetic forces are at play.

Onset of cabbeling instabilities in superconfined two-fluid systems

Convective-driven mixing in permeable subsurface environments is relevant in engineering and natural systems. This process occurs in groundwater remediation, oil recovery, CO2 sequestration, and hydrothermal environments. When two fluids come into contact in superconfined geometries like open fractures in rocks, complex molecular dynamics can develop at the fluid–fluid interface, creating a denser mixture and leading to cabbeling instabilities that propel solutal convection. Previous studies in superconfined systems have used models based on unstable density distributions—generating Rayleigh–Taylor instabilities—and analog fluid mixtures characterized by nonlinear equations of state—resulting in cabbeling dynamics—yet often neglecting interfacial tension effects, which is also relevant in miscible systems. This study incorporates the Korteweg tensor into the Hele–Shaw model to better understand the combined influence of geometry confinement and interfacial tension on the onset of cabbeling instabilities in two-fluid superconfined systems. Through direct numerical simulations, we investigate the system's stability, revealing that the onset, characterized by the critical time tc, exhibits a nonlinear relationship with the system's nondimensional parameters—the Rayleigh number Ra, the anisotropy ratio ϵ, and the Korteweg number Ko. This relationship is crystallized into a single scaling law tc=F(Ra,ϵ,Ko). Our findings indicate that geometry and effective interfacial tension exert a stabilizing effect during the initial stages of convection, stressing the necessity for further exploration of its influence on fluid mixing in superconfined systems.

Thermal equation of state of Li-rich schorl up to 15.5 GPa and 673 K: Implications for lithium and boron transport in slab subduction

Abstract The thermal equation of state (EoS) of a natural schorl has been determined at high temperatures up to 673 K and high pressures up to 15.5 GPa using in situ synchrotron X-ray diffraction combined with a diamond-anvil cell. The pressure-volume (P-V) data were fitted to a third-order Birch-Murnaghan EoS with V0 = 1581.45 ± 0.25 Å3, K0 = 111.6 ± 0.9 GPa, and K0′ = 4.4 ± 0.2; additionally, when K0′ was fixed at a value of 4, V0 = 1581.04 ± 0.20 Å3, and K0 = 113.6 ± 0.3 GPa. The V0 (1581.45 ± 0.25 Å3) obtained by the third-order Birch-Murnaghan EoS agrees well with the V0 (1581.45 ± 0.05 Å3) measured at ambient conditions. Furthermore, the axial compression data of schorl at room temperature were fitted to a “linearized” third-order Birch-Murnaghan EoS, and the obtained axial moduli for the a- and c-axes are Ka = 621 ± 9 GPa and Kc = 174 ± 2 GPa, respectively. Consequently, the axial compressibilities are βa = 1.61 × 10–3 GPa–1 and βc = 5.75 × 10–3 GPa–1 with an anisotropic ratio of βa:βc = 0.28:1.00, indicating axial compression anisotropy. In addition, the compositional effect on the axial compressibilities of tourmalines was discussed. Fitting our pressure-volume-temperature (P-V-T) data to a high-temperature third-order Birch-Murnaghan EoS yielded the following thermal EoS parameters: V0 = 1581.2 ± 0.2 Å3, K0 = 110.5 ± 0.6 GPa, K0′ = 4.6 ± 0.2, (∂KT/∂T)P = –0.012 ± 0.003 GPa K–1 and αV0 = (2.4 ± 0.2) × 10–5 K–1. These parameters were compared with those of previous studies on other tourmalines, and the potential factors influencing the thermal EoS parameters of tourmalines were further discussed.

Enhanced Optoelectronic Performance and Polarized Sensitivity in WSe2 Nanoscrolls Through Quasi-One-Dimensional Structure.

Transition metal dichalcogenides (TMDs), such as tungsten diselenide (WSe2), are expected to be used in next-generation optoelectronic devices due to their unique properties. In this study, we developed a simple method of using ethanol to scroll monolayer WSe2 nanosheets into nanoscrolls. These nanoscrolls have a quasi-one-dimensional structure, which enhances their electronic and optical properties. The characterization confirmed their unique structure, and the photodetectors made of these nanoscrolls have high sensitivity to polarized light, with anisotropy ratios of 1.3 and 1.7 at wavelengths of 638 nm and 808 nm. The enhanced light response is attributed to the large surface area and quantum wire-like behavior of the nanoscrolls, making them suitable for advanced polarization-sensitive devices.