The effect of iron concentration on the microstructural and structural properties of ZnO for electrolysis and photodetector applications was investigated.The thin layers of un-doped and doped ZnO with different percen...The effect of iron concentration on the microstructural and structural properties of ZnO for electrolysis and photodetector applications was investigated.The thin layers of un-doped and doped ZnO with different percentages of Fe(2,4,and 6 wt.%)were deposited by spin-coating on glass substrates.Sample characterization was done by X-ray diffraction(XRD),atomic force microscopy(AFM),scanning electron microscopy(SEM),energy-dispersive X-ray spectroscopy(EDS),UV−Vis absorption spectra and X-ray photoelectron spectroscopy(XPS).Structural measurements by XRD showed that all the layers were composed of polycrystallines with a hexagonal Wurtzite structure.Two new peaks were also discovered after the doping process belonging to the Fe_(2)O_(4)(400)and(440)crystal phase.Morphological analysis showed that the surface roughness values of ZnO layers ranged between 8 and 45 nm.XPS studies confirmed the presence of Fe in 3+states in ZnO layers.An average transmittance of 90%was measured by UV−Vis in the wavelength range of 200−900 nm.The values of the energy gap(Eg)decreased with an increase in the concentration of Fe.AFM topography results confirmed that ZnO-based thin layers had a relatively uniform surface.The efficiency of these samples has been confirmed for their use in many electrical applications,including photodetectors and electrolysis of contaminated solutions.展开更多
What factors fundamentally determine the value of superconducting transition temperature Tc in high temperature superconductors has been the subject of intense debate.Following the establishment of an empirical law kn...What factors fundamentally determine the value of superconducting transition temperature Tc in high temperature superconductors has been the subject of intense debate.Following the establishment of an empirical law known as Homes'law,there is a growing consensus in the community that the Tc value of the cuprate superconductors is closely linked to the superfluid density(ρ_(s))of its ground state and the conductivity(σ)of its normal state.However,all the data supporting this empirical law(ρ_(s)=AσT_(c))have been obtained from the ambientpressure superconductors.In this study,we present the first high-pressure results about the connection of the quantities ofρ_(s)andσwith T_(c),through the studies on the Bi_(1.74)Pb_(0.38)Sr_(1.88)CuO_(6+δ)and Bi_(2)Sr_(2)CaCu_(2)O_(8+δ),in which the value of their high-pressure resistivity(ρ=1/σ)is achieved by adopting our newly established method,while the quantity ofρs is extracted using Homes'law.We highlight that the Tc values are strongly linked to the joint response factors of magnetic field and electric field,i.e.,ρ_(s)andσ,respectively,implying that the physics determining T_(c)is governed by the intrinsic electromagnetic fields of the system.展开更多
We study the existence and stability of envelope solitons on a continuous-wave background in a non-Kerr quintic optical material exhibiting a self-steepening effect.Light propagation in such a nonlinear medium is gove...We study the existence and stability of envelope solitons on a continuous-wave background in a non-Kerr quintic optical material exhibiting a self-steepening effect.Light propagation in such a nonlinear medium is governed by the Gerdjikov-Ivanov equation.We find that the system supports a variety of localized waveforms exhibiting an important frequency chirping property which makes them potentially useful in many practical applications to optical communication.This frequency chirp is found to be crucially dependent on the intensity of the wave and its amplitude can be controlled by a suitable choice of self-steepening parameter.The obtained nonlinearly chirped solitons include bright,gray and kink shapes.We also discuss the stability of the chirped solitons numerically under finite initial perturbations.The results show that the main character of chirped localized structures is not influenced by finite initial perturbations such as white noise.展开更多
Complex oxide interfaces have been one of the central focuses in condensed matter physics and ma-terial science.Over the past decade,aberration corrected scanning transmission electron microscopy and spectroscopy has ...Complex oxide interfaces have been one of the central focuses in condensed matter physics and ma-terial science.Over the past decade,aberration corrected scanning transmission electron microscopy and spectroscopy has proven to be invaluable to visualize and understand the emerging quantum phenomena at an interface.In this paper,we briefly review some recent progress in the utilization of electron microscopy to probe interfaces.Specifically,we discuss several important challenges for electron microscopy to advance our understanding on interface phenomena,from the perspective of variable temperature,magnetism,electron energy loss spectroscopy analysis,electronic symmetry,and defects probing.展开更多
The multiferroic ceramics Bi_(0.8)Ba_(0.2)Fe_(1-x)Sb_(x)O_(3)with x=0,0.01,and 0.02 were synthesized using the solid-phase reaction technique.The samples were sintered at two different temperatures,850℃and 900℃.Scan...The multiferroic ceramics Bi_(0.8)Ba_(0.2)Fe_(1-x)Sb_(x)O_(3)with x=0,0.01,and 0.02 were synthesized using the solid-phase reaction technique.The samples were sintered at two different temperatures,850℃and 900℃.Scanning electron microscopy revealed the effect of antimony concentration on grain size and formation.The effect of Sb-doping on the crystal structure and ferroelectric properties of these ceramics was investigated using X-ray diffraction,Raman spectroscopy,and dielectric measurements.The dielectric constant was enhanced upon Fe^(3+)substitution by Sb^(3+)without affecting the dielectric loss of the ceramics.The tetragonal distortion of the rhombohedral symmetry of BiFeO_(3)caused by Ba-doping at Bi 3þsite was lifted by Sb-doping at Fe^(3+)site.展开更多
基金the support received from the Researchers Supporting Project(No.RSP2024R404),King Saud University,Riyadh,Saudi Arabia。
文摘The effect of iron concentration on the microstructural and structural properties of ZnO for electrolysis and photodetector applications was investigated.The thin layers of un-doped and doped ZnO with different percentages of Fe(2,4,and 6 wt.%)were deposited by spin-coating on glass substrates.Sample characterization was done by X-ray diffraction(XRD),atomic force microscopy(AFM),scanning electron microscopy(SEM),energy-dispersive X-ray spectroscopy(EDS),UV−Vis absorption spectra and X-ray photoelectron spectroscopy(XPS).Structural measurements by XRD showed that all the layers were composed of polycrystallines with a hexagonal Wurtzite structure.Two new peaks were also discovered after the doping process belonging to the Fe_(2)O_(4)(400)and(440)crystal phase.Morphological analysis showed that the surface roughness values of ZnO layers ranged between 8 and 45 nm.XPS studies confirmed the presence of Fe in 3+states in ZnO layers.An average transmittance of 90%was measured by UV−Vis in the wavelength range of 200−900 nm.The values of the energy gap(Eg)decreased with an increase in the concentration of Fe.AFM topography results confirmed that ZnO-based thin layers had a relatively uniform surface.The efficiency of these samples has been confirmed for their use in many electrical applications,including photodetectors and electrolysis of contaminated solutions.
基金supported by the National Key Research and Development Program of China(Grant Nos.2021YFA1401800 and 2022YFA1403900)the National Natural Science Foundation of China(Grant Nos.U2032214,12122414,12104487,and 12004419)+1 种基金the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(Grant No.XDB25000000)supported by the US Department of Energy,Office of Basic Energy Sciences(Grant No.DOE-sc0012704)。
文摘What factors fundamentally determine the value of superconducting transition temperature Tc in high temperature superconductors has been the subject of intense debate.Following the establishment of an empirical law known as Homes'law,there is a growing consensus in the community that the Tc value of the cuprate superconductors is closely linked to the superfluid density(ρ_(s))of its ground state and the conductivity(σ)of its normal state.However,all the data supporting this empirical law(ρ_(s)=AσT_(c))have been obtained from the ambientpressure superconductors.In this study,we present the first high-pressure results about the connection of the quantities ofρ_(s)andσwith T_(c),through the studies on the Bi_(1.74)Pb_(0.38)Sr_(1.88)CuO_(6+δ)and Bi_(2)Sr_(2)CaCu_(2)O_(8+δ),in which the value of their high-pressure resistivity(ρ=1/σ)is achieved by adopting our newly established method,while the quantity ofρs is extracted using Homes'law.We highlight that the Tc values are strongly linked to the joint response factors of magnetic field and electric field,i.e.,ρ_(s)andσ,respectively,implying that the physics determining T_(c)is governed by the intrinsic electromagnetic fields of the system.
基金supported by the Ministry of Education’s Industry School Cooperation Collaborative Education Project of China under grant number 220405078262706.
文摘We study the existence and stability of envelope solitons on a continuous-wave background in a non-Kerr quintic optical material exhibiting a self-steepening effect.Light propagation in such a nonlinear medium is governed by the Gerdjikov-Ivanov equation.We find that the system supports a variety of localized waveforms exhibiting an important frequency chirping property which makes them potentially useful in many practical applications to optical communication.This frequency chirp is found to be crucially dependent on the intensity of the wave and its amplitude can be controlled by a suitable choice of self-steepening parameter.The obtained nonlinearly chirped solitons include bright,gray and kink shapes.We also discuss the stability of the chirped solitons numerically under finite initial perturbations.The results show that the main character of chirped localized structures is not influenced by finite initial perturbations such as white noise.
基金supported by the US Department of Energy(DOE)under Grant No.DOE DE-SC0002136.Z.W.and Y.Z.acknowledge the support by the U.S.Department of Energy,Office of Basic Energy Science,Division of Materials Science and Engineering,under contract no.DESC0012704H.G.acknowledges the support by Shanghai Municipal Natural Science Foundation(No.19ZR1402800)Shanghai Municipal Natural Science Foundation(No.18JC1411400).
文摘Complex oxide interfaces have been one of the central focuses in condensed matter physics and ma-terial science.Over the past decade,aberration corrected scanning transmission electron microscopy and spectroscopy has proven to be invaluable to visualize and understand the emerging quantum phenomena at an interface.In this paper,we briefly review some recent progress in the utilization of electron microscopy to probe interfaces.Specifically,we discuss several important challenges for electron microscopy to advance our understanding on interface phenomena,from the perspective of variable temperature,magnetism,electron energy loss spectroscopy analysis,electronic symmetry,and defects probing.
文摘The multiferroic ceramics Bi_(0.8)Ba_(0.2)Fe_(1-x)Sb_(x)O_(3)with x=0,0.01,and 0.02 were synthesized using the solid-phase reaction technique.The samples were sintered at two different temperatures,850℃and 900℃.Scanning electron microscopy revealed the effect of antimony concentration on grain size and formation.The effect of Sb-doping on the crystal structure and ferroelectric properties of these ceramics was investigated using X-ray diffraction,Raman spectroscopy,and dielectric measurements.The dielectric constant was enhanced upon Fe^(3+)substitution by Sb^(3+)without affecting the dielectric loss of the ceramics.The tetragonal distortion of the rhombohedral symmetry of BiFeO_(3)caused by Ba-doping at Bi 3þsite was lifted by Sb-doping at Fe^(3+)site.
