期刊文献+
共找到20篇文章
< 1 >
每页显示 20 50 100
量子隧道态-声子耦合系统的变分法研究
1
作者 石云龙 聂一行 +1 位作者 陈鸿 吴翔 《物理学报》 SCIE EI CAS CSCD 北大核心 1992年第9期1499-1503,共5页
本文采用变分法研究了量子隧道态-声子耦合系统的基态能量。发现:系统的基态可以用位移态及位移-压缩态这两种变分态描述,且随着耦合强度的增加,稳定的基态将由位移态向位移-压缩态转变。本文给出这种转变的相图。
关键词 量子隧道态 声子 耦合 变分法
原文传递
玻璃中两能级隧道态耦合态及其对低频声吸收的影响
2
作者 王国梁 《物理学报》 SCIE EI CAS CSCD 北大核心 1997年第5期938-947,共10页
讨论了在声子作用下,两能级隧道态耦合态激发和退激发规律。
关键词 隧道态 玻璃 耦合 非晶 低温热学异常
原文传递
Blasting induced dynamic stress concentration and failure characteristics of deep-buried rock tunnel
3
作者 ZHAO Rui TAO Ming +2 位作者 XIANG Gong-liang WANG Shao-feng ZHAO Hua-tao 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2321-2340,共20页
In this study,the dynamic stress concentration factors(DSCF)around a straight-wall arch tunnel(SWAT)were solved analytically utilizing the complex variable function methods and Duhamel’s integral.The effects of wavel... In this study,the dynamic stress concentration factors(DSCF)around a straight-wall arch tunnel(SWAT)were solved analytically utilizing the complex variable function methods and Duhamel’s integral.The effects of wavelength,incident angle,and blasting rising time on the DSCF distribution were analyzed.Theoretical results pointed out dynamic disturbances resulting in compressive stress concentration in the vertical direction and tensile stress in the incident direction.As the wavelength and rising time increased,there was a tendency for the amplitude of stress concentration to initially rise and then converge.Moreover,a series of 3D FEM models were established to evaluate the effect of different initial stress states on the dynamic failure of the tunnel surrounding rock.The results indicated that the failure of the surrounding rock was significantly influenced by the direction of the static maximum principal stress and the direction of the dynamic disturbance.Under the coupling of static and blasting loading,damage around the tunnel was more prone to occur in the dynamic and static stress concentration coincidence zone.Finally,the damage modes of rock tunnel under static stress and blasting disturbance from different directions were summarized and a proposed support system was presented.The results reveal the mechanisms of deep-buried rock tunnel destruction and dynamically triggered rockburst. 展开更多
关键词 stress wave scattering dynamic stress analysis rock tunnel dynamic failure analysis
下载PDF
Designand development of highway tunnel maintenance and management system 被引量:4
4
作者 葛敏莉 孙璐 《Journal of Southeast University(English Edition)》 EI CAS 2015年第1期137-142,共6页
In order to solve the urgent problem of how to manage and sustain highway tunnels with advanced information technology with the background of the rapid development in the modem traffic, and achieve the cost- effective... In order to solve the urgent problem of how to manage and sustain highway tunnels with advanced information technology with the background of the rapid development in the modem traffic, and achieve the cost- effectiveness optimal principle objectives under the premise of guaranteeing a smooth flow of traffic; a highway tunnel maintenance and management system framework and the key modules were proposed. First, the determined highway tunnel condition assessment index system was established according to the result of expert consulting forms. Secondly, the tunnel diseases, the corresponding maintenance measurements, and many-to-many relationship between diseases and maintenance measurements were introduced. Then, three kinds of 0-1 integer programming models were built according to different tunnel operators' needs in the optimization decision module. Finally, the further development and implementation of the system was prospected. The research results can provide references to tunnel researchers and managers. 展开更多
关键词 maintenance and management system highwaytunnel condition assessment distress treatment cost-benefitanalysis
下载PDF
Determination of minimum cover depth for shallow tunnel subjected to water pressure 被引量:5
5
作者 HUANG Fu QIN Chang-bing LI Shu-cai 《Journal of Central South University》 SCIE EI CAS 2013年第8期2307-2313,共7页
Prediction of the state of roof collapse is a big challenge in tunnel engineering, while the limit analysis theory makes it possible to derive the analytical solutions of the collapse mechanisms. In this work, an exac... Prediction of the state of roof collapse is a big challenge in tunnel engineering, while the limit analysis theory makes it possible to derive the analytical solutions of the collapse mechanisms. In this work, an exact solution of collapsing shape in shallow underwater tunnel is obtained by using the variation principle and the upper bound theorem based on nonlinear failure criterion. Numerical results under the effect of river water and supporting pressure are derived and discussed. The maximum water depth above the river bottom surface is determined under a given buried depth of shallow cavities and the critical depth of roof collapse is obtained under a constant river depth. In comparison with the previous results, the present solution shows a good agreement with the practical results. 展开更多
关键词 shallow underwater subway roof collapse nonlinear failure criterion
下载PDF
Teleportation of a Kind of Three-Mode Entangled States of Continuous Variables 被引量:1
6
作者 FAN Hong-Yi LIANG Xian-Ting 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5X期833-836,共4页
A quantum teleportation scheme to teleport a kind of tripartite entangled states of continuous variables by using a quantum channel composed of three bipartite entangled states is proposed. The joint Bell measurement ... A quantum teleportation scheme to teleport a kind of tripartite entangled states of continuous variables by using a quantum channel composed of three bipartite entangled states is proposed. The joint Bell measurement is feasible because the bipartite entangled states are complete and the squeezed state has a natural representation in the entangled state basis. The calculation is greatly simplified by using the Schmidt decomposition of the entangled states. 展开更多
关键词 three-mode entangled state of continuous variables TELEPORTATION squeezed state
下载PDF
Enhancing the hydration reactivity of hemi-hydrate phosphogypsum through a morphology-controlled preparation technology 被引量:6
7
作者 Lin Yang Jianxin Cao Caiyu Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第9期1298-1305,共8页
The distribution of water channels in the crystal morphology of type-α hemi-hydrated gypsum(α-HH) was theoretically detected to investigate the effect of water channels on the hydration reactivity of hemi-hydrate ph... The distribution of water channels in the crystal morphology of type-α hemi-hydrated gypsum(α-HH) was theoretically detected to investigate the effect of water channels on the hydration reactivity of hemi-hydrate phosphogypsum(HPG). Results showed that water channels were mainly distributed in the cylinders of α-HH crystal,whereas no water channel existed in the conical surfaces parallel to the z-axis. Increasing the number of water channels was critical to enhance the hydration activity of HPG compared with the hydration reactivity of industrial HPG and type-α high-strength gypsum. Controlling the technological parameters of crystallization by concentration of liquid-phase SO_4^(2-) made it possible to obtain HPG which had the stumpy crystals of α-HH and high hydration reactivity. 展开更多
关键词 Hydration reactivity Morphology-controlled Water channel Hemi-hydrated phosphogypsum
下载PDF
Limiting drainage criterion for groundwater of mountain tunnel 被引量:1
8
作者 程盼 赵炼恒 +2 位作者 李亮 邹金锋 罗伟 《Journal of Central South University》 SCIE EI CAS 2014年第12期4660-4668,共9页
Large amount of groundwater discharging from tunnel is likely to cause destruction of the ecological environment in the vicinity of the tunnel, thus an appropriate drainage criterion should be established to balance t... Large amount of groundwater discharging from tunnel is likely to cause destruction of the ecological environment in the vicinity of the tunnel, thus an appropriate drainage criterion should be established to balance the tunnel construction and groundwater.To assess the related problems, an limiting drainage standard ranging from 0.5 to 2.0 m3/(m·d) was suggested for mountain tunnels based on survey and comparative analysis. After that, for the purpose of verifying the rationality of the standard, a calculated formula for dewatering funnel volume caused by drainage was deduced on the basis of the groundwater dynamics and experience method.Furthermore, the equation about the relationship between water discharge and drawdown of groundwater table was presented. The permeability coefficient, specific yield and groundwater table value were introduced, and then combined with the above equation, the drawdown of groundwater table under the proposed limiting drainage criterion was calculated. It is shown that the proposed drainage standard can reach the purpose of protecting ecological environment under the following two conditions. One is the permeability coefficient ranges from 10-4 to 10-5 m/s and the specific yield ranges from 0.1 to 0.001. The other is the permeability coefficient varies from 10-6 to 10-8 m/s and the specific yield varies from 0.1 to 0.01. In addition, a majority of common geotechnical layers are involved in the above ranges. Thus, the proposed limiting drainage standard which ranges from 0.5 to 2.0 m3/(m·d) for mountain tunnel is reasonable. 展开更多
关键词 mountain tunnel groundwater dewatering funnel limiting drainage criterion drawdown of groundwater table
下载PDF
Structure of Reconstructed Cu(100) Surface Induced by Dissociative Adsorption of Gaseous Oxygen
9
作者 窦卫东 张寒洁 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第1期18-22,I0001,共6页
The reconstructed structures of Cu(100) surface induced by O2 dissociative adsorption were investigated by low energy electron diffraction and scanning tunneling microscopy. At lower oxygen coverage, it was found th... The reconstructed structures of Cu(100) surface induced by O2 dissociative adsorption were investigated by low energy electron diffraction and scanning tunneling microscopy. At lower oxygen coverage, it was found that two reconstructed structures, i.e. c(2×2)-O and (√2×2√2)R45°-O are coexistent. The domain size of the c(2×2)-O structure decreased with the increasing of O2 exposure. The reconstructed structure at very small coverage was also investigated and a “zigzag” structure was observed at this stage. The “zigzag” structure was identified as boundaries of local c(2×2) domains. It was found that the strip region shows much stronger molecule-substrate interaction than that of oxygen covered regions, making it a proper template for patterned organic films. The sequence of the thermal stability was found as zigzag structure〉c(2×2)〉(√2×2√2)R45°-O. 展开更多
关键词 Surface reconstruction Chemical adsorption Scanning tunneling microscopy Structural phase transition
下载PDF
Multiuser Pre-Coding Aided Quadrature Spatial Modulation for Large-Scale MIMO Channels 被引量:1
10
作者 Fatang Chen Kang Yang +2 位作者 Pingping Xing Huan Zhang Yanan Jiang 《China Communications》 SCIE CSCD 2018年第11期62-69,共8页
Pre-coding aided quadrature spatial modulation(PQSM) is a promising multiple input multiple output(MIMO) transmission technology. The multiuser(MU) detection in PQSM system is investigated in this paper. Based on the ... Pre-coding aided quadrature spatial modulation(PQSM) is a promising multiple input multiple output(MIMO) transmission technology. The multiuser(MU) detection in PQSM system is investigated in this paper. Based on the known channel state information, pre-coding matrix is designed to pre-process the in-phase and quadrature signals of quadrature spatial modulation(QSM) to reduce the inter-channel interference. In order to lower the complexity at the receiver brought by the orthogonality of the PQSM system, an orthogonal matching pursuit(OMP) detection algorithm and a reconstructed model are proposed. The analysis and simulation results show that the proposed algorithm can obtain a similar bit error rate(BER) performance as the maximum likelihood(ML) detection algorithm with more than 80% reduction of complexity. 展开更多
关键词 pre-coding generalized quadra-ture spatial modulation bit error performance maximum likelihood
下载PDF
The mitigation negative effect of tunnel-blasting-induced vibrations on constructed tunnel and buildings
11
作者 LIN Da-neng 《Journal of Coal Science & Engineering(China)》 2011年第1期28-33,共6页
Provided the results of a research conducted to investigate the relationships between the empirical vibration attenuation equation of Peak Particle Velocity (PPV) and the Scaled Charge (SC) through testing the bla... Provided the results of a research conducted to investigate the relationships between the empirical vibration attenuation equation of Peak Particle Velocity (PPV) and the Scaled Charge (SC) through testing the blasting-induced vibrations on the spot of Wanshishan tunnel based on 96 vibration recordings. It is found that the maximum charge amount per delay in Wanshishan tunnel excavating is determined by the buildings on the surface and the constructed tunnel nearby. Considering that the repeated blast loading in tunnel blasting caused accumulative effects of damage on buildings, comfortable threshold damage limits of PPV to maintain buildings safety was given. Dynamic Stress Ratio (DSR) was adopted to study the stability of constructed tunnel on the action of blasting induced vibrations. The method to determine specific maximum charge amount per delay in Wanshishan tunnel excavation was given. It is proved that the findings in this study are very effective to control the negative effects of blasting-induced vibrations on buildings on the surface and constructed tunnel nearby. 展开更多
关键词 blasting-induced vibration tunnel blasting threshold damage limits maximum charge amount per delay
下载PDF
STUDY ON THE METHODS OF STRUCTURALDYNAMIC MODIFICATION OPTIMIZATION OF ROAD HEADERS
12
作者 吴淼 黄民 +1 位作者 王建军 魏任之 《Journal of China University of Mining and Technology》 1996年第2期62-68,共7页
In this paper, taking AM-50 Road Heaer as an example, the metheds of structural dynamic modification optimization for road headers are studied using experimental modal analysis and physical parameters analysis. The ma... In this paper, taking AM-50 Road Heaer as an example, the metheds of structural dynamic modification optimization for road headers are studied using experimental modal analysis and physical parameters analysis. The machine’s modal model and lumped mass model are established and the vibration response simulation is calculated for the two models with the load spectral measured. On the above basis, the dynamic parameters of the models are optimised and some useful results have been obtained.The research methods in this paper can be used for the reference to the other lager type mining machines. 展开更多
关键词 tunneling machine road headers structural dynamic medification
下载PDF
Predictive analysis of stress regime and possible squeezing deformation for super-long water conveyance tunnels in Pakistan
13
作者 Wang Chenghu Bao Linhai 《International Journal of Mining Science and Technology》 SCIE EI 2014年第6期825-831,共7页
The prediction of the stress field of deep-buried tunnels is a fundamental problem for scientists and engineers. In this study, the authors put forward a systematic solution for this problem. Databases from the World ... The prediction of the stress field of deep-buried tunnels is a fundamental problem for scientists and engineers. In this study, the authors put forward a systematic solution for this problem. Databases from the World Stress Map and the Crustal Stress of China, and previous research findings can offer prediction of stress orientations in an engineering area. At the same time, the Andersonian theory can be used to analyze the possible stress orientation of a region. With limited in-situ stress measurements, the Hock-Brown Criterion can be used to estimate the strength of rock mass in an area of interest by utilizing the geotechnical investigation data, and the modified Sheorey's model can subsequently be employed to predict the areas' stress profile, without stress data, by taking the existing in-situ stress measurements as input parameters. In this paper, a case study was used to demonstrate the application of this systematic solution. The planned Kohala hydropower plant is located on the western edge of Qinghai-Tibet Plateau. Three hydro-fracturing stress measurement campaigns indicated that the stress state of the area is SH - Sh 〉 Sv or SH 〉Sv 〉 Sh. The measured orientation of Sn is NEE (N70.3°-89°E), and the regional orientation of SH from WSM is NE, which implies that the stress orientation of shallow crust may be affected by landforms. The modified Sheorey model was utilized to predict the stress profile along the water sewage tunnel for the plant. Prediction results show that the maximum and minimum horizontal principal stres- ses of the points with the greatest burial depth were up to 56.70 and 40.14 MPa, respectively, and the stresses of areas with a burial depth of greater than 500 m were higher. Based on the predicted stress data, large deformations of the rock mass surrounding water conveyance tunnels were analyzed. Results showed that the large deformations will occur when the burial depth exceeds 300 m. When the burial depth is beyond 800 m, serious squeezing deformations will occur in the surrounding rock masses, thus requiring more attention in the design and construction. Based on the application efficiency in this case study, this prediction method proposed in this paper functions accurately. 展开更多
关键词 Super-long water conveyance tunnel In-situ stress state Squeezing deformation Prediction analysis Kohala hydropower plant
下载PDF
Continuous-Variable Entanglement in Tunnel-Coupled Double Quantum Wells
14
作者 Lü Xin-You LIU Ji-Bing HAO Xiang-Ying HUANG Pei YANG Xiao-Xue 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第5期831-838,共8页
This paper investigates the generation and evolution of continuous-variable entanglement in an asymmetric coupled-quantum well (CQW) system. Our numerical results show that this CQW system can be regarded as a sourc... This paper investigates the generation and evolution of continuous-variable entanglement in an asymmetric coupled-quantum well (CQW) system. Our numerical results show that this CQW system can be regarded as a source of macroscopic entangled light over a wide range of initial states of the cavity field. This investigation can be used for achieving the macroscopic entangled light in the CQW solid-state medium, which is much more praeticaJ than that in an atomic medium because of its flexible design and the controllable interference strength. 展开更多
关键词 continuous-variable entanglement semiconductor quantum well
下载PDF
Tunneling Conductance in a Normal Metal/Ferromagnetic Superconductor Nano-Junction at a Finite Temperature
15
作者 Hamidreza Emamipour M.R.Abolhassani 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第1期171-175,共5页
In this study, we investigate the tunneling conductance at a finite temperature in a normal metal/ferromagnetic superconductor nano-junction where the ferromagnetic superconductor (FS) is in three different cooper p... In this study, we investigate the tunneling conductance at a finite temperature in a normal metal/ferromagnetic superconductor nano-junction where the ferromagnetic superconductor (FS) is in three different cooper pairing states: spin singlet s-wave pairing (SWP), spin triplet opposite spin pairing (OSP), and spin triplet equal spin pairing (ESP) while including Fermi wave mismatch (FWM) and effective mass mismatch (EMM) in two sides of the nano-junction. We find that the conductance shows clearly different behaviors all depending on the symmetries of cooper pairing in a manner that the conductance spectra shows a gap-like structure, two interior dips structure and zero bias peak for SWP, OSP, and ESP, respectively. Also, the effective FS gap (Δeff) is a linear and decreasing function of exchange field. The slope of (Δeff) versus exchange field for OSP is twice the SWP. Thus, we can determine the spin polarization of N/FS nano-junction based on the dependence of (Δeff) to exchange field. 展开更多
关键词 spin singlet s-wave pairing spin triplet opposite spin pairing spin triplet equal spin pairing
下载PDF
Tunneling Dynamics Between Atomic and Molecular Bose-Einstein Condensates
16
作者 CHENChang-Yong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第4期547-552,共6页
Tunneling dynamics of multi-atomic molecules between atomic and multi-atomic molecular Bose-Einstein condensates with Feshbach resonance is investigated.It is indicated that the tunneling in the two Bose-Einstein cond... Tunneling dynamics of multi-atomic molecules between atomic and multi-atomic molecular Bose-Einstein condensates with Feshbach resonance is investigated.It is indicated that the tunneling in the two Bose-Einstein condensates depends on not only the inter-atomic-molecular nonlinear interactions and the initial number of atoms in these condensates,but also the tunneling coupling between the atomic condensate and the multi-atomic molecular condensate.It is discovered that besides oscillating tunneling current between the atomic condensate and the multi-atomic molecular condensate,the nonlinear multi-atomic molecular tunneling dynamics sustains a self-locked population imbalance:a macroscopic quantum self-trapping effect.The influence of de-coherence caused by non-condensate atoms on the tunneling dynamics is studied.It is shown that de-coherence suppresses the multi-atomic molecular tunneling.Moreover,the conception of the molecular Bose-Einstein condensate,which is different from the conventional single-atomic Bose-Einstein condensate,is specially emphasized in this paper. 展开更多
关键词 tunneling dynamics an atomic(a molecular)Bose-Einstein condensate Feshbach resonance DECOHERENCE
下载PDF
Sufficient Conditions of the Same State Order Induced by Coherence 被引量:1
17
作者 Pu-Gang Zhang Yong-Ming Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2018年第8期137-144,共8页
In this paper, we study coherence-induced state ordering with Tsallis relative entropy of coherence, relative entropy of coherence and l1 norm of coherence, and give the sufficient conditions of the same state order i... In this paper, we study coherence-induced state ordering with Tsallis relative entropy of coherence, relative entropy of coherence and l1 norm of coherence, and give the sufficient conditions of the same state order induced by above coherence measures. First, we show that the above measures give the same ordering for single-qubit states in some special cases. Second, we consider some special states in a d-dimensional quantum system. We show that the above measures generate the same ordering for these special states. Finally, we discuss dynamics of coherence-induced state ordering under Markovian channels. We find amplitude damping channel changes the coherence-induced ordering even though for single-qubit states with fixed mixedness. 展开更多
关键词 Tsallis relative entropy of coherence relative entropy of coherence l1 norm of coherence coherence-induced state ordering
原文传递
Nodeless pairing in superconducting copper-oxide monolayer films on BieSreCaCueO8+δ 被引量:9
18
作者 Yong Zhong Yang Wang +13 位作者 Sha Han Yan-Feng Lv Wen-Lin Wang Ding Zhang Hao Ding Yi-Min Zhang Lili Wang Ke He Ruidan Zhong John A. Schneeloch Gen-Da Gu Can-Li Song Xu-Cun Ma Qi-Kun Xue 《Science Bulletin》 SCIE EI CAS CSCD 2016年第16期1239-1247,共9页
The pairing mechanism of high-temperature superconductivity in cuprates remains the biggest unresolved mystery in condensed matter physics. To solve the problem, one of the most effective approaches is to investigate ... The pairing mechanism of high-temperature superconductivity in cuprates remains the biggest unresolved mystery in condensed matter physics. To solve the problem, one of the most effective approaches is to investigate directly the superconducting CuO2 layers. Here, by growing CuO2 monolayer films on Bi2Sr2CaCu2O8+δ substrates, we identify two distinct and spatially separated energy gaps centered at the Fermi energy, a smaller U-like gap and a larger V-like gap on the films, and study their interactions with alien atoms by low-temperature scanning tunneling microscopy. The newly discovered U-like gap exhibits strong phase coherence and is immune to scattering by K, Cs and Ag atoms, suggesting its nature as a nodeless superconducting gap in the CuO2 layers, whereas the V-like gap agrees with the well-known pseudogap state in the underdoped regime. Our results support an s-wave superconductivity in Bi2Sr2CaCu2O8+δ, which, we pro- pose, originates from the modulation-doping resultant twodimensional hole liquid confined in the CuO2 layers. 展开更多
关键词 Copper oxides Molecular beam epitaxy Nodeless pairing Modulation doping
原文传递
Imaging the atomic-scale electronic states induced by a pair of hole dopants in Ca_(2)CuO_(2)Cl_(2) Mott insulator
19
作者 Haiwei Li Shusen Ye +2 位作者 Jianfa Zhao Changqing Jin Yayu Wang 《Science Bulletin》 SCIE EI CSCD 2021年第14期1395-1400,M0003,共7页
We use scanning tunneling microscopy to visualize the atomic-scale electronic states induced by a pair of hole dopants in Ca_(2)CuO_(2)Cl_(2)parent Mott insulator of cuprates.We find that when the two dopants approach... We use scanning tunneling microscopy to visualize the atomic-scale electronic states induced by a pair of hole dopants in Ca_(2)CuO_(2)Cl_(2)parent Mott insulator of cuprates.We find that when the two dopants approach each other,the transfer of spectral weight from high energy Hubbard band to low energy ingap state creates a broad peak and nearly V-shaped gap around the Fermi level.The peak position shows a sudden drop at distance around 4 a_(0)and then remains almost constant.The in-gap states exhibit peculiar spatial distributions depending on the configuration of the two dopants relative to the underlying Cu lattice.These results shed important new lights on the evolution of low energy electronic states when a few holes are doped into parent cuprates. 展开更多
关键词 CUPRATES Mott insulator Charge transfer gap Impurity state Scanning tunneling microscopy
原文传递
Nanoscale superconductivity of ?-Ga islands grown by molecular beam epitaxy
20
作者 ZHANG HuiMin PENG JunPing +6 位作者 GUAN JiaQi LI Zhi SONG CanLi WANG LiLi HE Ke MA XuCun XUE QiKun 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2015年第10期89-93,共5页
We report on the preparation and superconductivity of metastable γ-Ga islands on Si(111) substrate. The Ga grows in a typical Volmer-Weber mode at a low temperature of 110 K, resulting in formation of Ga nanoislands ... We report on the preparation and superconductivity of metastable γ-Ga islands on Si(111) substrate. The Ga grows in a typical Volmer-Weber mode at a low temperature of 110 K, resulting in formation of Ga nanoislands at various sizes with the identical γ-phase. In-situ low temperature scanning tunneling spectra reveal quantized electronic states in ultrathin Ga islands. It is found that both the lateral size and thickness of the Ga islands strongly suppress the superconductivity. Due to substantial surface energy contribution, the transition temperature Tc scales inversely with the island thickness and the minimum thickness for the occurrence of superconductivity is calculated to be two monolayers. 展开更多
关键词 γ-Ga SUPERCONDUCTIVITY size effects molecular beam epitaxy
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部