期刊文献+
共找到30篇文章
< 1 2 >
每页显示 20 50 100
Optimal Error Estimates of the Semi-Discrete Local Discontinuous Galerkin Method and Exponential Time Differencing Schemes for the Thin Film Epitaxy Problem without Slope Selection
1
作者 Danni Zhang Ruihan Guo 《Advances in Applied Mathematics and Mechanics》 SCIE 2023年第3期545-567,共23页
In this paper,we prove the optimal error estimates in L2 norm of the semidiscrete local discontinuous Galerkin(LDG)method for the thin film epitaxy problem without slope selection.To relax the severe time step restric... In this paper,we prove the optimal error estimates in L2 norm of the semidiscrete local discontinuous Galerkin(LDG)method for the thin film epitaxy problem without slope selection.To relax the severe time step restriction of explicit time marching methods,we employ a class of exponential time differencing(ETD)schemes for time integration,which is based on a linear convex splitting principle.Numerical experiments of the accuracy and long time simulations are given to show the efficiency and capability of the proposed numerical schemes. 展开更多
关键词 Local discontinuous Galerkin method thin film epitaxy problem error estimates exponential time differencing long time simulation
原文传递
Exploring heteroepitaxial growth and electrical properties of α-Ga_(2)O_(3) films on differently oriented sapphire substrates
2
作者 Wei Wang Shudong Hu +7 位作者 Zilong Wang Kaisen Liu Jinfu Zhang Simiao Wu Yuxia Yang Ning Xia Wenrui Zhang Jichun Ye 《Journal of Semiconductors》 EI CAS CSCD 2023年第6期46-51,共6页
This study explores the epitaxial relationship and electrical properties of α-Ga_(2)O_(3) thin films deposited on a-plane, mplane, and r-plane sapphire substrates. We characterize the thin films by X-ray diffraction ... This study explores the epitaxial relationship and electrical properties of α-Ga_(2)O_(3) thin films deposited on a-plane, mplane, and r-plane sapphire substrates. We characterize the thin films by X-ray diffraction and Raman spectroscopy, and elucidate thin film epitaxial relationships with the underlying sapphire substrates. The oxygen vacancy concentration of α-Ga_(2)O_(3) thin films on m-plane and r-plane sapphire substrates are higher than α-Ga_(2)O_(3) thin film on a-plane sapphire substrates. All three thin films have a high transmission of over 80% in the visible and near-ultraviolet regions, and their optical bandgaps stay around 5.02–5.16 eV. Hall measurements show that the α-Ga_(2)O_(3) thin film grown on r-plane sapphire has the highest conductivity of 2.71 S/cm, which is at least 90 times higher than the film on a-plane sapphire. A similar orientation-dependence is seen in their activation energy as revealed by temperature-dependent conductivity measurements, with 0.266, 0.079, and 0.075eV for the film on a-, m-, r-plane, respectively. The origin of the distinct transport behavior of films on differently oriented substrates is suggested to relate with the distinct evolution of oxygen vacancies at differently oriented substrates. This study provides insights for the substrate selection when growing α-Ga_(2)O_(3) films with tunable transport properties. 展开更多
关键词 gallium oxide thin film epitaxy ORIENTATION oxygen vacancy electrical properties
下载PDF
Growth of β-Ga_2O_3 Films on Sapphire by Hydride Vapor Phase Epitaxy 被引量:3
3
作者 Ze-Ning XIONG Xiang-Qian XIU +7 位作者 Yue-Wen LI Xue-Mei HUA Zi-Li XIE Peng CHEN Bin LIU Ping HAN Rong ZHANG You-Dou ZHENG 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第5期141-143,共3页
Two-inch Ga_2O_3 films with(ˉ201)-orientation are grown on c-sapphire at 850–1050°C by hydride vapor phase epitaxy. High-resolution x-ray diffraction shows that pure β-Ga_2O_3 with a smooth surface has a hig... Two-inch Ga_2O_3 films with(ˉ201)-orientation are grown on c-sapphire at 850–1050°C by hydride vapor phase epitaxy. High-resolution x-ray diffraction shows that pure β-Ga_2O_3 with a smooth surface has a higher crystal quality, and the Raman spectra reveal a very small residual strain in β-Ga_2O_3 grown by hydride vapor phase epitaxy compared with bulk single crystal. The optical transmittance is higher than 80% in the visible and near-UV regions, and the optical bandgap energy is calculated to be 4.9 e V. 展开更多
关键词 Growth of Ga2O3 films on Sapphire by Hydride Vapor Phase epitaxy XRD
下载PDF
Molecular Beam Epitaxy Growth of Tetragonal FeS Films on SrTiO3(001) Substrates
4
作者 赵琨 林海城 +4 位作者 黄万通 胡小鹏 陈曦 薛其坤 季帅华 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第8期125-128,共4页
We report the successful growth of the tetragonal FeS film with one or two unit-cell (UC) thickness on SrTiO33(001) substrates by molecular beam epitaxy. Large lattice constant mismatch with the substrate leads to... We report the successful growth of the tetragonal FeS film with one or two unit-cell (UC) thickness on SrTiO33(001) substrates by molecular beam epitaxy. Large lattice constant mismatch with the substrate leads to high density of defects in single-UC FeS, while it has been significantly reduced in the double-UC thick film due to the lattice relaxation. The scanning tunneling spectra on the surface of the FeS thin film reveal the electronic doping effect of single-UC FeS from the substrate. In addition, at the Fermi level, the energy gaps of approximately 1.5?meV are observed in the films of both thicknesses at 4.6?K and below. The absence of coherence peaks of gap spectra may be related to the preformed Cooper-pairs without phase coherence. 展开更多
关键词 FES UC SUBSTRATES Molecular Beam epitaxy Growth of Tetragonal FeS films on SrTiO3
下载PDF
Tuning the Electronic Structure of Sr2IrO4 Thin Films by Bulk Electronic Doping Using Molecular Beam Epitaxy
5
作者 李明颖 刘正太 +7 位作者 杨海峰 赵家琳 姚岐 樊聪聪 刘吉山 高波 沈大伟 谢晓明 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第5期124-128,共5页
By means of oxide molecular beam epitaxy with shutter-growth mode, we fabricate a series of electron-doped (Sr1-xLax)2IrO4 (001) (x=0, 0.05, 0.1 and 0.15) single crystalline thin films and then investigate the d... By means of oxide molecular beam epitaxy with shutter-growth mode, we fabricate a series of electron-doped (Sr1-xLax)2IrO4 (001) (x=0, 0.05, 0.1 and 0.15) single crystalline thin films and then investigate the doping dependence of the electronic structure utilizing in-situ angle-resolved photoemission spectroscopy. It is found that with the increasing doping content, the Fermi levels of samples progressively shift upward. Prominently, an extra electron pocket crossing the Fermi level around the M point is evidently observed in the 15% nominal doping sample. Moreover, bulk-sensitive transport measurements confirm that the doping effectively suppresses the insulating state with respect to the as-grown Sr2IrO4, though the doped samples still remain insulating at low temperatures due to the localization effect possibly stemming from disorders including oxygen deficiencies. Our work provides another feasible doping method to tune electronic structure of Sr2 IrO4. 展开更多
关键词 Sr Tuning the Electronic Structure of Sr2IrO4 Thin films by Bulk Electronic Doping Using Molecular Beam epitaxy RHEED La ARPES
下载PDF
Growth of a-Plane GaN Films on r-Plane Sapphire by Combining Metal Organic Vapor Phase Epitaxy with the Hydride Vapor Phase Epitaxy
6
作者 姜腾 许晟瑞 +3 位作者 张进成 林志宇 蒋仁渊 郝跃 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第8期173-176,共4页
Hydride vapor phase epitaxy (HVPE) is utilized to grow nonpolar a-plane GaN layers on r-plane sapphire templates prepared by metal organic vapor phase epitaxy (MOVPE). The surface morphology and microstructures of... Hydride vapor phase epitaxy (HVPE) is utilized to grow nonpolar a-plane GaN layers on r-plane sapphire templates prepared by metal organic vapor phase epitaxy (MOVPE). The surface morphology and microstructures of the samples are characterized by atomic force microscopy. The full width at half maximum (FWHM) of the HVPE sample shows a W-shape and that of the MOVPE sample shows an M-shape plane with the degree of 0 in the high-resolution x-ray diffraction (HRXRD) results. The surface morphology attributes to this significant anisotropic. HRXRD reveals that there is a significant reduction in the FWHM, both on-axis and off-axis for HVPE GaN are compared with the MOVPE template. The decrease of the FWHM of E2 (high) Raman scat tering spectra further indicates the improvement of crystal quality after HVPE. By comparing the results of secondary- ion-mass spectroscope and photoluminescence spectrum of the samples grown by HVPE and MOVPE, we propose that C-involved defects are originally responsible for the yellow luminescence. 展开更多
关键词 MOVPE GAN Growth of a-Plane GaN films on r-Plane Sapphire by Combining Metal Organic Vapor Phase epitaxy with the Hydride Vapor Phase epitaxy
下载PDF
Oxygen vacancy control of electrical,optical,and magnetic properties of Fe_(0.05)Ti_(0.95)O_(2) epitaxial films
7
作者 Qing-Tao Xia Zhao-Hui Li +7 位作者 Le-Qing Zhang Feng-Ling Zhang Xiang-Kun Li Heng-Jun Liu Fang-Chao Gu Tao Zhang Qiang Li Qing-Hao Li 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第11期575-579,共5页
High-quality Fe-doped TiO_(2) films are epitaxially grown on MgF_(2) substrates by pulsed laser deposition.The x-ray diffraction and Raman spectra prove that they are of pure rutile phase.High-resolution transmission ... High-quality Fe-doped TiO_(2) films are epitaxially grown on MgF_(2) substrates by pulsed laser deposition.The x-ray diffraction and Raman spectra prove that they are of pure rutile phase.High-resolution transmission electron microscopy(TEM)further demonstrates that the epitaxial relationship between rutile-phased TiO_(2) and MgF_(2) substrates is 110 TiO_(2)||110 MgF_(2).The room temperature ferromagnetism is detected by alternative gradient magnetometer.By increasing the ambient oxygen pressure,magnetization shows that it decreases monotonically while absorption edge shows a red shift.The transport property measurement demonstrates a strong correlation between magnetization and carrier concentration.The influence of ambient oxygen pressure on magnetization can be well explained by a modified bound magnetization polarization model. 展开更多
关键词 ferromagnetic materials SEMICONDUCTORS epitaxial films rutile TiO_(2)
下载PDF
Substrate Effect on the Structural and Electrical Properties of LaNiO_(3) Thin Films
8
作者 YAO Dan WANG Weiwei +1 位作者 YU Jiangying YOU Yuwei 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2022年第4期559-563,共5页
Epitaxial LaNiO_(3)(LNO)thin films prepared from the sols modified with polyethyleneimine(PEI)were grown on single-crystal LaAlO_(3),(LaAlO_(3))_(0.3)(SrAlTaO_(6))_(0.7),and SrTiO_(3) substrates,respectively,using a s... Epitaxial LaNiO_(3)(LNO)thin films prepared from the sols modified with polyethyleneimine(PEI)were grown on single-crystal LaAlO_(3),(LaAlO_(3))_(0.3)(SrAlTaO_(6))_(0.7),and SrTiO_(3) substrates,respectively,using a simple polymer assisted deposition(PAD).The epitaxial structure,surface morphologies and transport of the LNO films were studied by X-ray diffraction(θ/2θ symmetric scan,ω-scan,and in-planeφ-scan),the field emission scanning electron microscopy,and a standard dc four-probe method.It is found that,compared with that of LNO bulk,the c-axis parameter of the LNO film increases under compressive strain and decreases under tensile strain.All the LNO films exhibit metal properties in the temperature-dependent resistivity.The resistivity of the LNO films shows an increasing trend with the lattice mismatch strain changing from compressive to tensile.It is suggested that the oxygen vacancy compensated by more Ni^(2+)changed from Ni^(3+)in the film increases with the strain changing from compressive to tensile,which results in the increase of the resistivity. 展开更多
关键词 NICKELATES electrical properties epitaxial film polymer assisted deposition
下载PDF
First-principles study of FeSe epitaxial films on SrTiO_3
9
作者 刘凯 高淼 +1 位作者 卢仲毅 向涛 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第11期10-14,共5页
The discovery of high temperature superconductivity in FeSe films on SrTiO3 substrate has inspired great experimen- tal and theoretical interests. First-principles density functional theory calculations, which have pl... The discovery of high temperature superconductivity in FeSe films on SrTiO3 substrate has inspired great experimen- tal and theoretical interests. First-principles density functional theory calculations, which have played an important role in the study of bulk iron-based superconductors, also participate in the investigation of interfacial superconductivity. In this article, we review the calculation results on the electronic and magnetic structures of FeSe epitaxial films, emphasiz- ing on the interplay between different degrees of freedom, such as charge, spin, and lattice vibrations. Furthermore, the comparison between FeSe monolayer and bilayer films on SrTiO3 is discussed. 展开更多
关键词 iron-based superconductor first-principles calculations epitaxial film
下载PDF
Anomalous Hall effect of facing-target sputtered ferrimagnetic Mn_(4)N epitaxial films with perpendicular magnetic anisotropy
10
作者 Zeyu Zhang Qiang Zhang Wenbo Mi 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第4期653-659,共7页
Epitaxial Mn_(4)N films with different thicknesses were fabricated by facing-target reactive sputtering and their anomalous Hall effect(AHE)is investigated systematically.The Hall resistivity shows a reversed magnetic... Epitaxial Mn_(4)N films with different thicknesses were fabricated by facing-target reactive sputtering and their anomalous Hall effect(AHE)is investigated systematically.The Hall resistivity shows a reversed magnetic hysteresis loop with the magnetic field.The magnitude of the anomalous Hall resistivity sharply decreases with decreasing temperature from300 K to 150 K.The AHE scaling law in Mn_(4)N films is influenced by the temperature-dependent magnetization,carrier concentration and interfacial scattering.Different scaling laws are used to distinguish the various contributions of AHE mechanisms.The scaling exponentγ>2 for the conventional scaling in Mn_(4)N films could be attributed to the residual resistivityρ_(xx0).The longitudinal conductivityσ_(xx)falls into the dirty regime.The scaling ofρ_(AH)=αρ_(xx0)+bρ_(xx)~nis used to separate out the temperature-independentρ_(xx0)from extrinsic contribution.Moreover,the relationship betweenρ_(AH)and pxx is fitted by the proper scaling to clarify the contributions from extrinsic and intrinsic mechanisms of AHE,which demonstrates that the dominant mechanism of AHE in the Mn4 N films can be ascribed to the competition between skew scattering,side jump and the intrinsic mechanisms. 展开更多
关键词 Mn_(4)N epitaxial film anomalous Hall effect scaling law
下载PDF
Fe-doped epitaxial YBCO films prepared by chemical solution deposition
11
作者 Hong Zhang Yong Zhao +2 位作者 Wentao Wang Min Pan Ming Lei 《Journal of Modern Transportation》 2014年第1期45-49,共5页
YBa2Cu3O7-d (YBCO)-coated conductors havewide-ranging potential in large-scale applications such assuperconducting maglev trains and superconducting electriccables, but low current carrying capability restrains thep... YBa2Cu3O7-d (YBCO)-coated conductors havewide-ranging potential in large-scale applications such assuperconducting maglev trains and superconducting electriccables, but low current carrying capability restrains thepractical application of YBCO-coated conductors at hightemperatures and high magnetic fields. It is crucial todevelop YBCO-coated conductors with high critical currentdensity. In this paper, epitaxial, dense, smooth, andcrack-free Fe-doped YBCO films were prepared on aLaAlO3 single crystal substrate via a fluorine-free polymerassistedmetal organic deposition method. The effects ofthe dilute Fe doping on microstructure and superconductingcharacter of YBCO films were investigated. The criticaltemperature for superconducting of the Fe-dopedYBCO films decreases slightly. However, the in-fieldcritical current density of YBCO films improves with diluteFe doping of amounts less than x = 0.005, compared to thepure YBCO film. Therefore, the current carrying capabilityof YBCO film can improve by doping with appropriateamounts of Fe. This means that dilute Fe doping in YBCOfilms may be a feasible way to prepare high-performancecoated conductors. 展开更多
关键词 Epitaxial films Fe doping SUPERCONDUCTOR Coated conductor
下载PDF
Effect of Oxygen Partial Pressure on Epitaxial Growth and Properties of Laser-Ablated AZO Thin Films
12
作者 王传彬 LUO Sijun +1 位作者 SHEN Qiang 张联盟 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第1期27-30,共4页
Al-doped ZnO(AZO) thin films were grown on c-sapphire substrates by laser ablation under different oxygen partial pressures(P_(O2)).The effect of P_(O2) on the crystal structure,preferred orientation as well a... Al-doped ZnO(AZO) thin films were grown on c-sapphire substrates by laser ablation under different oxygen partial pressures(P_(O2)).The effect of P_(O2) on the crystal structure,preferred orientation as well as the electrical and optical properties of the films was investigated.The structure characterizations indicated that the as-grown films were single-phased with a wurtzite ZnO structure,showing a significant c-axis orientation.The films were well crystallized and exhibited better crystallinity and denser texture when deposited at higher P_(O2).At the optimum oxygen partial pressures of 10- 15 Pa,the AZO thin films were epitaxially grown on c-sapphire substrates with the(0001) plane parallel to the substrate surface,i e,the epitaxial relationship was AZO(000 1) // A1_2O_3(000 1).With increasing P_(O2),the value of Hall carrier mobility was increased remarkably while that of carrier concentration was decreased slightly,which led to an enhancement in electrical conductivity of the AZO thin films.All the films were highly transparent with an optical transmittance higher than 85%. 展开更多
关键词 AZO thin films epitaxial growth laser ablation oxygen partial pressure electrical and optical properties
下载PDF
Bipolar Resistive Switching in Epitaxial Mn_3O_4 Thin Films on Nb-Doped SrTiO_3 Substrates
13
作者 来旭波 王宇航 +4 位作者 石晓兰 李东勇 刘伯旸 王荣明 张留碗 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第6期112-115,共4页
Spinel (O01)-orientated Mn304 thin films on Nb-doped SrTi03 (001) substrates are fabricated via the pulsed laser deposition method. X-ray diffraction and high-resolution transmission electron microscopy indicate t... Spinel (O01)-orientated Mn304 thin films on Nb-doped SrTi03 (001) substrates are fabricated via the pulsed laser deposition method. X-ray diffraction and high-resolution transmission electron microscopy indicate that the as-prepared epitaxial fihn is well crystaiHzed. In the film plane the orientation relationship between the film and the substrate is [lOOjMn3 04 ||[110] Nb-doped SrTiO3. After an electroforming process, the film shows bipolar nonvolatile resistance switching behavior. The positive voltage bias drives the sample into a low resistance state, while the negative voltage switches it back to a high resistance state. The switching polarity is different from the previous studies. The complex impedance measurement suggests that the resistance switching behavior is of filament type. Due to the performance reproducibility and state stability, Mn3O4 might be a promising candidate for the resistive random access memory devices. 展开更多
关键词 HRS is of LRS in Bipolar Resistive Switching in Epitaxial Mn3O4 Thin films on Nb-Doped SrTiO3 Substrates on MN
下载PDF
Grain boundary boosting the thermal stability of Pt/CeO_(2)thin films
14
作者 Luyao Wang Xiaobao Li +10 位作者 Xiangchen Hu Shuyue Chen Zhehao Qiu Yifan Wang Hui Zhang Yi Yu Bo Yang Yong Yang Pasquale Orgiani Carmela Aruta Nan Yang 《Nano Research》 SCIE EI CSCD 2023年第2期3278-3286,共9页
Understanding how defect chemistry of oxide material influences the thermal stability of noble metal dopant ions plays an important role in designing high-performance heterogeneous catalytic systems.Here we use in-sit... Understanding how defect chemistry of oxide material influences the thermal stability of noble metal dopant ions plays an important role in designing high-performance heterogeneous catalytic systems.Here we use in-situ ambient-pressure X-ray photoemission spectroscopy(APXPS)to experimentally determine the role of grain boundary in the thermal stability of platinum doped cerium oxide(Pt/CeO_(2)).The grain boundaries were introduced in Pt/CeO_(2)thin films by pulsed laser deposition without significantly change of the surface microstructure.The defect level was tuned by the strain field obtained using a highly/low mismatched substrate.The Pt/CeO_(2)thin film models having well defined crystallographic properties but different grain boundary structural defect levels provide an ideal platform for exploring the evolution of Pt–O–Ce bond with changing the temperature in reducing conditions.We have direct demonstration and explanation of the role of Ce^(3+)induced by grain boundaries in enhancing Pt2+stability.We observe that the Pt^(2+)–O–Ce^(3+)bond provides an ideal coordinated site for anchoring of Pt^(2+)ions and limits the further formation of oxygen vacancies during the reduction with H_(2).Our findings demonstrate the importance of grain boundary in the atomic-scale design of thermally stable catalytic active sites. 展开更多
关键词 platinum doped cerium oxide(Pt/CeO_(2)) pulsed laser deposition epitaxial thin films grain boundaries defect engineering in-situ ambient-pressure X-ray photoemission spectroscopy
原文传递
Flexible oxide epitaxial thin films for wearable electronics:Fabrication,physical properties,and applications 被引量:8
15
作者 Wenlong Liu Hong Wang 《Journal of Materiomics》 SCIE EI 2020年第2期385-396,共12页
Recently,flexible oxide epitaxial thin films are of increasing interests owing to their excellent physical properties and wide applications.The oxide epitaxial thin films with flexible,lightweight and wearable are pro... Recently,flexible oxide epitaxial thin films are of increasing interests owing to their excellent physical properties and wide applications.The oxide epitaxial thin films with flexible,lightweight and wearable are promising for the applications in flexible and wearable devices,such as flexible sensors,flexible detectors,flexible oscillators,flexible spintronics,wearable displays and electronic skin,etc.This review aims to summarize the fabrication,physical properties and applications of the flexible oxide epitaxial thin films for wearable electronics in most recent few years.The fabrication of flexible oxide epitaxial thin films reviewed here mainly includes the deposition on flexible substrates at high temperature and epitaxial lift-off(ELO)from rigid substrates.The physical properties and applications of flexible oxide epitaxial thin films reviewed here chiefly focus on the area of electricity and magnetism,including stable and tunable physical properties in the flexible oxide epitaxial thin films.In final,the perspectives and challenges of flexible oxide thin films for wearable electronics have been also addressed. 展开更多
关键词 FLEXIBLE Epitaxial thin films FABRICATION Physical properties
原文传递
Effect of elastic domains on electromechanical response of epitaxial ferroelectric films with a three-domain architecture 被引量:2
16
作者 Jun OUYANG Wei ZHANG +1 位作者 SPamir ALPAY Alexander LROYTBURD 《Journal of Advanced Ceramics》 SCIE CAS 2013年第1期1-10,共10页
Thermodynamics of(001)epitaxial ferroelectric films completely relaxed due to the formation of elastic domains with a three-domain architecture is presented.The polydomain structure and electromechanical response of s... Thermodynamics of(001)epitaxial ferroelectric films completely relaxed due to the formation of elastic domains with a three-domain architecture is presented.The polydomain structure and electromechanical response of such films are analyzed for two cases corresponding to immobile and mobile elastic domain walls.It is shown that immobile elastic domains provide additional constraint which increases the mechanical and electrical clamping,thereby significantly reducing the piezoelectric and dielectric responses.On the other hand,a polydomain ferroelectric film adapts to the variations in the applied electric field by reversible domain wall displacements in the case of mobile domain walls.The comparison of the theory with experiments shows that the elastic domain walls are mobile in the fully relaxed films of~1μm thickness.In addition,if the substrate constraint is reduced via decreasing lateral size of a polydomain ferroelectric film,its piezoresponse will increase dramatically,as is experimentally verified on small islands of polydomain ferroelectric films.The general conclusions can be readily applied to other constrained polydomain films. 展开更多
关键词 FERROELECTRICS DOMAINS epitaxial films domain wall THERMODYNAMICS electromechanical properties
原文传递
Error Estimate of a Second Order Accurate Scalar Auxiliary Variable (SAV) Numerical Method for the Epitaxial Thin Film Equation 被引量:2
17
作者 Qing Cheng Cheng Wang 《Advances in Applied Mathematics and Mechanics》 SCIE 2021年第6期1318-1354,共37页
A second order accurate(in time)numerical scheme is analyzed for the slope-selection(SS)equation of the epitaxial thin film growth model,with Fourier pseudo-spectral discretization in space.To make the numerical schem... A second order accurate(in time)numerical scheme is analyzed for the slope-selection(SS)equation of the epitaxial thin film growth model,with Fourier pseudo-spectral discretization in space.To make the numerical scheme linear while preserving the nonlinear energy stability,we make use of the scalar auxiliary variable(SAV)approach,in which a modified Crank-Nicolson is applied for the surface diffusion part.The energy stability could be derived a modified form,in comparison with the standard Crank-Nicolson approximation to the surface diffusion term.Such an energy stability leads to an H2 bound for the numerical solution.In addition,this H2 bound is not sufficient for the optimal rate convergence analysis,and we establish a uniform-in-time H3 bound for the numerical solution,based on the higher order Sobolev norm estimate,combined with repeated applications of discrete H¨older inequality and nonlinear embeddings in the Fourier pseudo-spectral space.This discrete H3 bound for the numerical solution enables us to derive the optimal rate error estimate for this alternate SAV method.A few numerical experiments are also presented,which confirm the efficiency and accuracy of the proposed scheme. 展开更多
关键词 Epitaxial thin film equation Fourier pseudo-spectral approximation the scalar auxiliary variable(SAV)method Crank-Nicolson temporal discretization energy stability optimal rate convergence analysis.
原文传递
Influence of oxygen treatment and temperature on electrical properties of the epitaxial Nb-doped SrTiO_3 films on silicon 被引量:1
18
作者 XIANG WenFeng WANG ShaoMin ZHAO Kun 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第10期2009-2011,共3页
We have fabricated the epitaxial Nb-doped SrTiO3(NbSTO) thin films on Si substrates using a TiN film as the buffer layer.The oxygen-treatment and temperature dependence of electrical properties has been investigated.O... We have fabricated the epitaxial Nb-doped SrTiO3(NbSTO) thin films on Si substrates using a TiN film as the buffer layer.The oxygen-treatment and temperature dependence of electrical properties has been investigated.Oxygen treatment showed the surface change of NbSTO films has immense influence on the resistance switching.The resistance ratio of two resistance states decreased after oxygen treatment.With tested-temperature rising,the resistance and resistance ratio of two resistance states increased.The resistance switching of Pt/NbSTO junction as a function of oxygen-treatment and temperature can be explained by the charge trapping and detrapping process in the Pt/NbSTO interface,which will help understand the resistance switching mechanism of oxides. 展开更多
关键词 epitaxial Nb-doped SrTiO3 films resistance switching temperature dependence oxygen treatment
原文传递
Probing nickelate superconductors at atomic scale:A STEM review
19
作者 Yihan Lei Yanghe Wang +4 位作者 Jiahao Song Jinxin Ge Dirui Wu Yingli Zhang Changjian Li 《Chinese Physics B》 SCIE EI CAS 2024年第9期2-11,共10页
The discovery of nickelate superconductors,including doped infinite-layer(IL)nickelates RNiO2(R=La,Pr,Nd),layered square-planar nickelate Nd6Ni5O12,and the Ruddlesden–Popper(RP)phase La3Ni2O7,has spurred immense inte... The discovery of nickelate superconductors,including doped infinite-layer(IL)nickelates RNiO2(R=La,Pr,Nd),layered square-planar nickelate Nd6Ni5O12,and the Ruddlesden–Popper(RP)phase La3Ni2O7,has spurred immense interest in fundamental research and potential applications.Scanning transmission electron microscopy(STEM)has proven crucial for understanding structure–property correlations in these diverse nickelate superconducting systems.In this review,we summarize the key findings from various modes of STEM,elucidating the mechanism of different nickelate superconductors.We also discuss future perspectives on emerging STEM techniques for unraveling the pairing mechanism in the“nickel age”of superconductivity. 展开更多
关键词 scanning transmission electron microscopy superconductivity epitaxial thin films nickelates
下载PDF
Ultrafast photoinduced strain in super-tetragonal PbTiO ferroelectric films
20
作者 Linxing Zhang Darui Sun +4 位作者 Maosheng Chai Xianran Xing Jun Chen Bingbing Zhang Jianjun Tian 《Science China Materials》 SCIE EI CAS CSCD 2021年第7期1679-1686,共8页
The ultrafast photoinduced strain(UPS)resulting from the coupling of piezoelectric and photovoltaic effects in ferroelectric has been focused in the last decade,endowing them with extensive applications including ultr... The ultrafast photoinduced strain(UPS)resulting from the coupling of piezoelectric and photovoltaic effects in ferroelectric has been focused in the last decade,endowing them with extensive applications including ultrafast optical memories,sensors and actuators with strain engineering.The mechanism of screening of the depolarization field by photoinduced carriers is generally accepted for UPS in ferroelectrics,while the thermal component of the strain is usually diluted as the offset and has not been systematically confronted,leading to unnecessary confusion.Herein,both the positive and negative thermal expansion effects in composite ferroelectric epitaxial films are investigated by use of high-repetition-rate ultrafast X-ray diffraction,along with the piezoelectric and photovoltaic effects.The coupling of the positive/negative thermal effects and the piezoelectric/photovoltaic effects in ultrafast strain is evidenced and can be regulated.The opposite lattice responses due to different thermal effects of the samples with different axial ratios are observed.The maximum UPS is up to 0.24%,comparable to that of conventional ferroelectric.The interaction between the thermal and ferroelectric effects in the induced strain could promote the diversified applications with the coupling of light,heat and electricity. 展开更多
关键词 FERROELECTRICS epitaxial films piezoelectric and photovoltaic thermal effect
原文传递
上一页 1 2 下一页 到第
使用帮助 返回顶部