Dome-like Shape Research Articles

Effect of electrostatic confinement on the dome-shaped superconducting phase diagram at the LaAlO3/SrTiO3 interface

The two-dimensional electron gas (2DEG) at the LaAlO\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$_3$$\\end{document}/SrTiO\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$_3$$\\end{document} (LAO/STO) interface exhibits gate-tunable superconductivity with a dome-like shape of critical temperature as a function of electron concentration. This behavior has not been unambiguously explained yet. Here, we develop a microscopic model based on the Schrödinger–Poisson approach to determine the electronic structure of the LAO/STO 2DEG, which we then apply to study the principal characteristics of the superconducting phase within the real-space pairing mean-field approach. For the electron concentrations reported in the experiment, we successfully reproduce the dome-like shape of the superconducting gap. According to our analysis such behavior results from the interplay between the Fermi surface topology and the gap symmetry, with the dominant extended s-wave contribution. Similarly as in the experimental report, we observe a bifurcation effect in the superconducting gap dependence on the electron density when the 2DEG is electrostatically doped either with the top gate or the bottom gate. Our findings explains the dome-shaped phase diagram of the considered heterostucture with good agreement with the experimental data which, in turn, strongly suggest the appearance of the extended s-wave symmetry of the gap in 2DEG at the LAO/STO interface.

Doping dependence of superconductivity on a honeycomb lattice within the framework of kinetic-energy-driven superconductivity

Unconventional superconductivity on a honeycomb lattice has received increasing interest since the discovery of graphene primarily due to the similarities between materials with a honeycomb lattice and cuprate superconductors. Many theoretical studies have been conducted on superconductivity on a honeycomb lattice, however, a consistent picture is still lacking. In this paper, we have extended the theory of kinetic-energy-driven superconductivity, which has been developed to investigate unconventional superconductivity in cuprate superconductors, to explore superconductivity on a honeycomb lattice within the t-J model. Our results demonstrate that the charge-carrier pair gap parameter with [Formula: see text]-wave symmetry exhibits a dome-like shape as a function of doping, with superconductivity emerging at a certain doping concentration and disappearing at high doping levels, similar to what has been observed in cuprate and cobaltate superconductors. Furthermore, the charge-carrier pair gap parameter decreases with increasing the value of [Formula: see text] (the ratio between the antiferromagnetic exchange coupling constant and the nearest-neighbor hopping integral), and approaches zero when [Formula: see text] reaches a sufficiently large value. This indicates that the antiferromagnetic order will suppress the superconducting state and a sufficiently strong exchange coupling will completely destroy the superconductivity. Taking into account our present results together with the corresponding results of cuprate and cobaltate superconductors, it appears that the dome-like shape of the doping dependence of the charge-carrier pair gap parameter may be a common feature in doped Mott insulators.

Significant Progress of Initiated Chemical Vapor Deposition in Manufacturing Soft Non-spherical Nanoparticles: Upgrading to the Condensed Droplet Polymerization Approach and Key Technological Aspects

Initiated chemical vapor deposition is a unique solvent-free and completely dry vapor-phase deposition technique used to synthesize organic polymer films. In this process, an activated initiator, monomer, and carrier gas are introduced into the reaction chamber simultaneously. This technique has been widely adopted. However, if the monomer and initiator are introduced into the chamber in stages—allowing gas-phase monomer deposition and condensation first, followed by initiator introduction and controlling the monomer partial pressure to be higher than the saturated vapor pressure—non-spherical polymer nanoparticles with dome-like shapes can be obtained. This advanced iCVD technique is referred to as the “Condensed Droplet Polymerization Approach”. This high monomer partial pressure gas-phase deposition is not suitable for forming uniformly composed iCVD films; but interestingly, it can rapidly obtain polymer nanodomes (PNDs). Using CDP technology, Franklin polymerized multifunctional nanodomes in less than 45 s, demonstrating a wide range of continuous particle size variations, from sub-20 nanometers to over 1 micron. This rapid synthesis included a variety of functional polymer nanodomes in just a matter of seconds to minutes. This review discusses the crucial process conditions of the Condensed Droplet Polymerization (CDP) Approach for synthesizing PNDs. The main focus of the discussion was on the two-step method for synthesizing PNDs, where the nucleation mechanism of PNDs, factors influencing their size, and the effect of pressure on the distinct condensation of monomer vapor into polymer nanodomes and polymer films were extensively explored.

First-principles calculation of electron-phonon coupling in doped KTaO3.

Background: Motivated by the recent experimental discovery of strongly surface-plane-dependent superconductivity at surfaces of KTaO 3 single crystals, we calculate the electron-phonon coupling strength, λ, of doped KTaO 3 along the reciprocal-space high-symmetry directions. Methods:Using the Wannier-function approach implemented in the EPW package, we calculate λ across the experimentally covered doping range and compare its mode-resolved distribution along the [001], [110] and [111] reciprocal-space directions. Results: We find that the electron-phonon coupling is strongest in the optical modes around the Γ point, with some distribution to higher k values in the [001] direction. The electron-phonon coupling strength as a function of doping has a dome-like shape in all three directions and its integrated total is largest in the [001] direction and smallest in the [111] direction, in contrast to the experimentally measured trends in critical temperatures. Conclusions: This disagreement points to a non-BCS character of the superconductivity. Instead, the strong localization of λ in the soft optical modes around Γ suggests an importance of ferroelectric soft-mode fluctuations, which is supported by our findings that the mode-resolved λ values are strongly enhanced in polar structures. The inclusion of spin-orbit coupling has negligible influence on our calculated mode-resolved λ values.

Electromagnetic response of cuprate superconductors with coexisting electronic nematicity

ABSTRACT The electronically nematic order has emerged as a key feature of cuprate superconductors, however, its correlation with the fundamental properties such as the electromagnetic response remains unclear. Here the nematic-order state strength dependence of the electromagnetic response in cuprate superconductors is investigated within the framework of the kinetic-energy-driven superconductivity. It is shown that a significant anisotropy of the electromagnetic response is caused by the electronic nematicity. In particular, in addition to the pure d-wave component of the superconducting gap, the pure s-wave component of the superconducting gap is generated by the electronic nematicity, therefore there is a coexistence and competition of the d-wave component and the s-wave component. This coexistence and competition leads to that the maximal condensation energy appears at around the optimal strength of the electronic nematicity, and then decreases in both the weak and strong strength regions, which in turn induces the enhancement of superconductivity, and gives rise to the dome-like shape of the nematic-order state strength dependence of the superfluid density.

Ab initio materials design of superconductivity in d9 nickelates

Motivated by the recent theoretical materials design of superconducting d9 nickelates for which the charge transfer from the NiO2 layer to the block layer is completely suppressed [M. Hirayama et al., Phys. Rev. B 101, 075107 (2020)], we perform a calculation based on the dynamical vertex approximation and obtain the phase diagram of RbCa2NiO3 and A2NiO2Br2, where A is a cation with a valence of 2.5+. We show that the phase diagram of these nickelates exhibits the same essential features as those found in cuprates. Namely, superconductivity appears upon hole-doping into an antiferromagnetic Mott insulator, and the superconducting transition temperature shows a dome-like shape. This demonstrates that the electron correlations play an essential role in nickelate superconductors, and we can control them by changing block layers.

A novel bifunctional protein PNU7 in CaCO3 polymorph formation: Vaterite stabilization and surface energy minimization

CaCO3, which occurs in three crystalline anhydrous polymorphs named calcite, aragonite, and vaterite, is always found in mineralized skeletons or growing shells of many marine organisms. However, understanding how these organisms achieve this control has been a significant challenge in biomineralization. In this work, we proposed a novel vaterite stabilizer acidic matrix protein PNU7 that existed in both prism and nacre of Pinctada fucata, and identified its functional domain DDDDDDHDDVEETED. Our experiments reveal that PNU7 triggers a stable large vaterite formation with Mg2+ deficiency even under low Ca2+. Increasing PNU7 in the calcium carbonate crystallization system with Mg2+ leads to a significant shrinking in crystal size and rising in nucleation quantity. Moreover, it converts an atomically rough dome-like shape to a smooth sphere on unsiliconized glass. These effects rescind after removing the asp-rich region at the C-terminus. We also find that decreasing pnu7 mRNA in vivo leads to nacreous inner surface growth substantially lessened. Thus, PNU7 may not only supply vaterite in shell formation but also involve the nacreous regulation via surface energy minimization.

Three-dimensional morphogenesis of the human diaphragm during the late embryonic and early fetal period: Analysis using T1-weighted and diffusion tensor imaging.

A precise understanding of human diaphragm development is essential in fetal medicine. To our knowledge, no previous study has attempted a three-dimensional (3-D) analysis and evaluation of diaphragmatic morphogenesis and development from the embryonic to the early fetal period. This study aimed to evaluate the morphogenesis and fibrous architecture of the developing human diaphragm during the late embryonic and early fetal periods. Fifty-seven human embryos and fetuses (crown-rump length [CRL]=8-88 mm) preserved at the Congenital Anomaly Research Center of Kyoto University and Shimane University were analyzed. 3-D morphogenesis and fiber orientation of the diaphragm were assessed using phase-contrast X-ray computed tomography, T1-weighted magnetic resonance imaging (T1W MRI), and diffusion tensor imaging (DTI). T1W MR images and DTI scans were obtained using a 7-T MR system. The diaphragm was completely closed at Carnegie stage (CS) 20 and gradually developed a dome-like shape. The diaphragm was already in contact with the heart and liver ventrally in the earliest CS16 specimen observed, and the adrenal glands dorsally at CS19 or later. In the fetal period, the diaphragm contacted the gastric fundus in samples with a CRL ≥41 mm, and the spleen in samples with a CRL ≥70 mm. The relative position of the diaphragm with reference to the vertebrae changed rapidly from CS16 to CS19. The most cranial point of the diaphragm was located between the 4th and 8th thoracic vertebrae, regardless of fetal growth, in samples with a CRL of ≥16 mm. Diaphragmatic thickness was nearly uniform (0.15-0.2 mm) across samples with a CRL of 8-41 mm. The sternal, costal, lumbar parts, and the area surrounding the esophageal hiatus thickened with growth in samples with a CRL of ≥46 mm. The thickness at the center of the diaphragm and the left and right hemidiaphragmatic domes did not increase with growth. Tractography showed that the fiber orientation of the sternal, costal, and lumbar parts became more distinct as growth progressed in CS19 or later. All fibers in the costal and lumbar regions ran toward the left and right hemidiaphragmatic domes, except for those running to the caval opening and esophageal hiatus. The fiber orientation patterns from the right and left crura surrounding the esophageal hiatus were classified into three types. Distinct fiber directions between the costal and sternal and between the costal and lumbar diaphragmatic parts were observable in samples with a CRL of ≥46 mm. Anterior costal and sternal fibers ran toward the center. Fiber tracts around the center and the left and right hemidiaphragmatic domes; between the costal and lumbar orientations; and between the costal and sternal orientations showed a tendency for decreasing fractional anisotropy values with fetal growth and showed less density than other areas. In conclusion, we used 3-D thickness assessment and DTI tractography to identify qualitative changes in the muscular and tendonous regions of the diaphragm during the embryonic and early fetal periods. This study provides information on normal human diaphragm development for the progression of fetal medicine and furthering the understanding of congenital anomalies.

The inner structure and kinematics of the Zvizdal-Zalisk and Brusyliv fault zones of the Ukrainian shield by the results of tectonophysical, magnetometrical data

In 2021, the tectonophysical measurements of cracking, structural-textural elements of rocks near Malyn, Radomyshl, Pohrebyshche, Buky, Kashperivka and magnetometric field studies of Zvizdal-Zalisk dyke were carried out. And also the deep seismic sounding data along II and VI geotravers were analyzed in order to purpose to finding out of the internal structure and kinematics of Zvizdal-Zalisk and Brusyliv fault zones of the Ukrainian Shield.
 According to our tectonophysical data, the studied rocks were formed under landslide deformation processes with alternating sublatitudinal and submeridional compression regimes, which correspond to the youngest Subbottsi-Moshoryn stage of faulting formation within the Ukrainian Shield (1.80—1.77 Ga), with subhorizontal axes of compression σ1 — 315° and tensile σ3 — 45°. Cracks and bands of gneisses of moderate dip are also widely developed in the study area. Established, that it has deformation throw regime with σ1 — 100/85°, σ3 — 280/05°, σ2 — 10/02°. Authors of article associate this deformation with formation of the main breeds Zvizdal-Zalisk dikes. Deformations of the Nemyriv faulting stage (1.99 Ga) were fixed at the intersection node of the Zvizdal-Zalisk faulting zone with Nemyriv fault zone (1.99 Ga). Stress field is σ1 — 301°, σ3 — 31° at the intersection node the Brusyliv fault zone with Nemyriv fault zone and it repeat main deformation strains of the Novograd-Volyn and Uman massifs (~2.05 Ga).
 By the data of the deep seismic sounding along II and VI Geotraverses, the Zvizdal-Zalisk fault zone enters the mantle all along, in the north and in the south. The crust structure in the study area has two layers of upper crust (VР=5,9–6,4 km/s),with intermittent low- (5,8—6,2 km/s) and high-velocity (6,3—6,9 km/s) horizons, the middle crust (6,4—6,9 km/s), and lower crust (6,9—7,0 km/s) that has a wavy dome-like shape with high differentiated velocity picture differing on both sides of the Central faulting area. The Bug megablock has a dome-like structure along all VI Geotraverse and is divided in half by the Zvizdal-Zalisk fault zone at the Moho discontinuity according to the data of the tomographic inversion along the velocity change gradient.
 By the magnetometric data, the Zvizdal-Zalisk fault zone lies almost fully within the regional minimum of the magnetic field (∆В)а,reg, which encompasses areas of the crust with minimum values of magnetization. The dyke was formed at the same time of the Korosten pluton formation and at activation of the Zvizdal-Zalisk fault zone. Its small depth confirms its crust origin; the variable sharp incline of the dyke’s parts is evidence of its subvertical falling which corresponds to the vertical position of the Zvizdal-Zalisk fault zone.
 The data on the chemical-mineralogical composition and position of mineral deposits suggest that the main regional structures which have influenced the metallogenic specialization of the region are the Zvizdal-Zaliska, Brusyliv, Nemyriv, Khmelniksk, Central, and Sarnensko-Varvarivka fault zones.

Unraveling local structure of molten salt KF-KCl-KI via molecular dynamics simulation

The detailed structure and kinetic properties of the KF-KCl-KI salt melts were studied in the work. This ternary system is widely used to produce high-purity silicon by electrodeposition. The melt was at the temperature of 1000 K, the values of the diffusion coefficients of ions were predominantly arranged in a sequence determined by the ratio of inverse atomic masses. The radial distribution function and structural factor for melt ions were obtained. The structure of each subsystem of like ions is characterized by the prevalence of rotational symmetry of the 5th order. In the case of the I- ion subsystem, asymmetry appears in the distributions of Voronoi polyhedra both in topological and metric features. The angular distributions determined by the method of statistical geometry for ions of all types have a specific dome-like shape and indicate that the arrangement of three ions on the same line is an extremely rare event.

Superconductivity with the enhanced upper critical field in the Pt-doped CuRh2Se4 spinel

We report the effect of Pt doping on the superconductivity in ${\mathrm{CuRh}}_{2}{\mathrm{Se}}_{4}$ spinel using a combined experimental and theoretical study. Our x-ray diffraction results reveal that the $\mathrm{Cu}{({\mathrm{Rh}}_{1\text{\ensuremath{-}}x}{\mathrm{Pt}}_{x})}_{2}{\mathrm{Se}}_{4} (0\ensuremath{\le}x\ensuremath{\le}0.35)$ crystallizes in the structure with a space group of $Fd\overline{3}m$ (No. 227), and the lattice parameter $a$ increases with Pt doping. The resistivity and magnetic susceptibility measurement results verify that the superconducting transition temperature (${T}_{c}$) forms a domelike shape with a maximum value of 3.84 K at $x=0.06$. It is also observed that the Pt doping slightly reduces the lower critical magnetic field from 220 Oe in ${\mathrm{CuRh}}_{2}{\mathrm{Se}}_{4}$ to 168 Oe in $\mathrm{Cu}{({\mathrm{Rh}}_{0.94}{\mathrm{Pt}}_{0.06})}_{2}{\mathrm{Se}}_{4}$, while it significantly enhances the upper critical magnetic field, reaching the maximum of 4.93 T in the $\mathrm{Cu}{({\mathrm{Rh}}_{0.94}{\mathrm{Pt}}_{0.06})}_{2}{\mathrm{Se}}_{4}$ sample. The heat capacity result indicates that the sample $\mathrm{Cu}{({{\mathrm{Rh}}_{0.}}_{91}{{\mathrm{Pt}}_{0.0}}_{9})}_{2}{\mathrm{Se}}_{4}$ is a bulk superconductor. First-principles calculations suggest that the Pt doping leads to a redshift of a density of state peak near the Fermi level, consistent with the domelike ${T}_{\mathrm{c}}$ observed experimentally.

Repeated underwater explosive forming: Experimental investigation and numerical modeling based on coupled Eulerian–Lagrangian approach

The main focus of the present research study is on developing a profound understanding of the free explosive forming of metallic plates using repeated underwater shock-wave loading. To this end, experimental and numerical investigations of plastic deformation of 3 mm thick Armco® Iron plates were performed. Two series of experiments were conducted on plates under single and repeated loading (up to three times) to better understand the advantages of the idea of using consecutive loading. Therefore, 12 g and 4 g PE4 explosive charges were respectively used for single and repeated loading. It was showed that the deformed shape of the plate varies from a flat deformation profile to conical- and dome-like shapes for single and repeated loading, respectively. Besides, the maximum thinning percentage that occurred at the plate center significantly decreased for the case of repeated loading. Additionally, considering the details of the whole forming process, numerical simulation of underwater blast loading and interaction between the solid surface and water was carried out using the coupled Eulerian–Lagrangian (CEL) method and verified by the conducted experiments. The verified model was further used to obtain the simulation results for the plate under single loading by 6.25 g explosive charge in which the plate experienced the same maximum permanent transverse deflection as obtained at the 3rd blast of repeated loading (4 g). Comparison of the results for the last two conditions illustrated excellent formability, smoothness in deformation profile and thickness, lower magnitude for the JC damage criterion, and lower von Mises stress distribution on the plate for the case of repeated loading. Therefore, repeated underwater explosive forming can be used as an alternative method for high-velocity sheet forming and mass production.

Enhancement of superconductivity by electronic nematicity in cuprate superconductors

ABSTRACT The cuprate superconductors are characterised by numerous ordering tendencies, with the electronically nematic order being the most distinct form of order. Here the intertwinement of the electronic nematicity with superconductivity in cuprate superconductors is studied based on the kinetic-energy-driven superconductivity. It is shown that the optimised takes a dome-like shape with the weak and strong strength regions on each side of the optimal strength of the electronic nematicity, where the optimised reaches its maximum. This dome-like shape nematic-order strength dependence of thus indicates that the electronic nematicity enhances superconductivity. Moreover, this nematic order induces the anisotropy of the electron Fermi surface, where although the original electron Fermi surface contour with the four-fold rotation symmetry is broken up into that with a residual twofold rotation symmetry, this electron Fermi surface contour with the twofold rotation symmetry still is truncated to form the disconnected Fermi arcs with the most spectral weight that locates at around the tips of the Fermi arcs. Concomitantly, these tips of the Fermi arcs connected by the scattering wave vectors construct an octet scattering model, however, the partial scattering wave vectors and their respective symmetry-corresponding partners occur with unequal amplitudes, leading to these electronically ordered states being broken both rotation and translation symmetries. As a natural consequence, the electronic structure is inequivalent between the and directions in momentum space. These anisotropic features of the electronic structure are also confirmed via the result of the autocorrelation of the single-particle excitation spectra, where the breaking of the rotation symmetry is verified by the inequivalence on the average of the electronic structure at the two Bragg scattering sites. The theory also indicates that the order parameter of the electronic nematicity achieves its maximum in the characteristic energy and then decreases rapidly as the energy moves away from the characteristic energy.

Effects of 4d transition metal Pd doping on the magnetic and superconducting properties of 112-type iron pnictide EuFeAs2

The recently discovered 112-type EuFeAs2 compound that shows complex Eu-spin magnetism provides a new platform to study the interplay between superconductivity (SC) and magnetism in iron pnictide superconductors. In this paper, by substituting Fe with the 4d transition metal (TM) Pd, we have synthesized a series of EuFe1−x Pd x As2 (0 ⩽ x ⩽ 0.08) samples and studied the doping effect on SC and magnetism by means of electrical transport and magnetization measurements. The systematic evolution of the lattice parameters indicates that the Pd atoms have been successfully substituted into the Fe sites. With Pd doping, the Fe-related spin density wave transition at in the parent phase is rapidly suppressed, and SC simultaneously emerges, exhibiting a domelike shape with a maximum onset transition temperature of around 18.5 K at x = 0.04. On the other hand, the Eu-related antiferromagnetic order at is suppressed very slowly and persists up to x = 0.08, covering the whole SC dome region. Also, the reentrant spin-glass and spin-reorientation transitions below remain unchanged with Pd doping. All these results indicate that the Eu spins have little effect on SC in EuFe1−x Pd x As2. Finally, based on the resistivity and magnetization data, the T − x phase diagram of EuFe1−x Pd x As2 is constructed and compared with those of 3d TMs Co/Ni and La doped ones.

Impact of spin-orbit interaction on the phase diagram and anisotropy of the in-plane critical magnetic field at the superconducting LaAlO3/SrTiO3 interface

The two-dimensional electron gas at the interface between ${\mathrm{LaAlO}}_{3}$ and ${\mathrm{SrTiO}}_{3}$ (LAO/STO) exhibits gate-tunable superconductivity with a characteristic domelike shape of the critical temperature (${T}_{c}$) in the phase diagram. As shown recently [Phys. Rev. B 102, 085420 (2020)], such an effect can be explained as a consequence of the extended $s\text{\ensuremath{-}}\mathrm{wave}$ symmetry of the gap within an intersite real space pairing scenario, leading to a good agreement between the experiment and theory. In this work, we turn to a detailed analysis of the influence of spin-orbit coupling on the LAO/STO phase diagram by considering separately the atomic component as well as the interorbital hopping induced by the broken inversion symmetry at the interface. In particular, we analyze the optimal carrier concentration for which the maximal ${T}_{c}$ is reached relative to the Lifshitz transition point. We find that the misalignment between the two can be significantly enhanced by the spin-orbit splitting of the bands, combined with the fact that superconductivity sets in when the Fermi level passes the anticrossing induced by the spin-orbital hybridization. In the presence of the external in-plane magnetic field, our calculations show fourfold anisotropy with the paramagnetic limit largely exceeded for ${B}_{||}$ directed along the high symmetry points [01] and [01]. The obtained electron concentration dependence of ${B}_{c||}$ reproduces the characteristic domelike shape reported in experiments and the estimated value of ${B}_{c||}$ corresponds to that measured experimentally.

The capacity of Anacardium occidentale L. to the environment: ability to C-stock and reduction of CO2 gas emissions (case study in Pondok Village, Ngadirojo, Wonogiri)

Cashew plants are generally evergreen, so they cover land throughout the year, have a dome-like canopy shape and thick leaves are thought to reduce CO2 emissions, one of the gas that triggered global warming that likely turn into climate change. The research aims to measure carbon stocks and reduce CO2 gas emissions in cashew nuts has been carried out in Pondok Village, Wonogiri, Central Java, one of the cashews growing centers in Indonesia. The method of determining plant samples was carried out on cashew crops by monoculture, the age groups (KU) were differentiated 1, 2, 3, 4 and 5, the measuring plots were determined purposively due to the limited population in the same age plot. Carbon stocks were analyzed using the allomeric method, while CO2 emissions were calculated descriptively. The results showed that cashew plants have the ability to increase carbon stocks and reduce CO2 gas emissions, this ability is kuadratic in line with plant KU. The highest carbon stock by KU 4 plants, the highest ability to reduce CO2 emissions is found in plants aged 30-40 years. The implications of research results on crop management related to emission reduction and increase in C-stock are discussed.

Pop-up kirigami for stiff, dome-like structures

In architecture and engineering, surfaces with positive Gaussian curvature such as domes are used for their high stiffness-to-weight ratios and efficiency in enclosing a volume. These curved shapes are difficult to create due to time-consuming or scale-limited processes. In recent years, origami and kirigami have risen as viable routes for the rapid fabrication of complex surfaces from flat sheets; however, these methods typically lead to systems that are overly flexible due to their high number of degrees of freedom. In this paper, we present a design for a pop-up kirigami system that achieves symmetric, positive Gaussian curvature by taking advantage of an internal infinitesimal mechanism. The system is fabricated from flat sheets using a hexagonal pattern, and the sheets remain flat locally as the system deforms into a dome-like shape. We investigate the internal mechanism and deformation modes of the system, revealing the flexible mode that creates dome-like curvature. We discuss geometric variations of the system and illustrate the possible shapes that result from changing the initial pattern parameters. Finally, we demonstrate the high stiffness of the system that arises from restricting its one flexible mode in its final, dome-like shape. The proposed pop-up kirigami system offers a method for fabricating dome-like surfaces with potential applications as deployable enclosures, concave reflectors, and more.

Curvature Induced by Deflection in Thick Meta-Plates.

The design of advanced functional devices often requires the use of intrinsically curved geometries that belong to the realm of non-Euclidean geometry and remain a challenge for traditional engineering approaches. Here, it is shown how the simple deflection of thick meta-plates based on hexagonal cellular mesostructures can be used to achieve a wide range of intrinsic (i.e., Gaussian) curvatures, including dome-like and saddle-like shapes. Depending on the unit cell structure, non-auxetic (i.e., positive Poisson ratio) or auxetic (i.e., negative Poisson ratio) plates can be obtained, leading to a negative or positive value of the Gaussian curvature upon bending, respectively. It is found that bending such meta-plates along their longitudinal direction induces a curvature along their transverse direction. Experimentally and numerically, it is shown how the amplitude of this induced curvature is related to the longitudinal bending and the geometry of the meta-plate. The approach proposed here constitutes a general route for the rational design of advanced functional devices with intrinsically curved geometries. To demonstrate the merits of this approach, a scaling relationship is presented, and its validity is demonstrated by applying it to 3D-printed microscale meta-plates. Several applications for adaptive optical devices with adjustable focal length and soft wearable robotics are presented.

Superfluid weight and Berezinskii-Kosterlitz-Thouless transition temperature of strained graphene

We obtain the superfluid weight and Berezinskii-Kosterlitz-Thouless (BKT) transition temperature for highly unconventional superconducting states with the coexistence of chiral d-wave superconductivity, charge density waves and pair density waves in the strained graphene. Our results show that the strain-induced flat bands can promote the superconducting transition temperature approximately 50% compared to that of the original doped graphene, which suggests that the flat-band superconductivity is a potential route to get superconductivity with higher critical temperatures. In particular, we obtain the superfluid weight for the pure superconducting pair-density-wave states from which the deduced superconducting transition temperature is shown to be much lower than the gap-opening temperature of the pair density wave, which is helpful to understand the phenomenon of the pseudogap state in high-Tc cuprate superconductors. Finally, we show that the BKT transition temperature versus doping for strained graphene exhibits a dome-like shape and it depends linearly on the spin-spin interaction strength.

Exploring structured scripting cartographic technique of GMT for ocean seafloor modeling: A case of the East Indian Ocean

This paper examines spatial variations in the geomorphology of the Ninety East Ridge (NER), located in the Indian Ocean. The NER is an extraordinary long linear bathymetric feature with topography reflecting complex geophysical setting and geologic evolution. The research is based on a compilation of high-resolution bathymetric, geological, and gravity datasets clipped for the study area extent (65° - 107°E, 35°S - 21°N): General Bathymetric Chart of the Oceans (GEBCO), Earth Gravitational Model (EGM2008, EGM96). The submarine geomorphology of the NER was modeled by digitized cross-sectional profiles using Generic Mapping Tools (GMT). The availability of the method is explained by 1) the free datasets; 2) the open source GMT toolset; 3) the available tutorials of the GMT and the codes explained in this work. Three segments of the NER were selected, digitized, and modeled: 1) northern 89°E, 7°S to 90°E, 7°N; 2) central 88.4°E, 14.7°S to 88.8°E, 8.2°S; 3) southern 87.9°E, 17°S to 87.5°E, 27°S. Measured depths were visualized in graphs, compared, and statistically analyzed by the histograms. The northern segment has a steepness of 21.3° at the western slopes, and 14.5° at the eastern slope. The slopes on the eastern flank have dominant SE orientation. The central segment has a bell-shaped form, with the highest steepness comparing to the northern and southern segments. The eastern flank has a steepness of 49.5°. A local depression at a distance of 50 km off from the axis (90°E) continues parallel to the NER, with the shape of the narrow minor trench. The western slope has a steepness of 57.6°, decreasing to 15.6°. The southern segment has a dome-like shape form. Compared to the northern and central segments, it has a less pronounced ridge crest, with a steepness of 24.9° on the west. The eastern flank has a steepness of 36.8° until 70 km, gradually becoming steeper at 44.23°. A local minor trench structure can be seen on its eastern flank (100 km off the axis). This corresponds to the very narrow long topographic depressions stretching parallel to this segment of the NER at 90.5°E. The study contributes to regional geographic studies of Indian Ocean geomorphology and cartographic presentation of GMT functionality for marine research and oceanographic studies.