An optimized device structure for reducing the RESET current of phase-change random access memory （PCRAM） with blade-type like （BTL） phase change layer is proposed. The electrical thermal analysis of the BTL cell ...An optimized device structure for reducing the RESET current of phase-change random access memory （PCRAM） with blade-type like （BTL） phase change layer is proposed. The electrical thermal analysis of the BTL cell and the blade heater contactor structure by three-dimensional finite element modeling are compared with each other during RESET operation. The simulation results show that the programming region of the phase change layer in the BTL cell is much smaller, and thermal electrical distributions of the BTL cell are more concentrated on the TiN/GST interface. The results indicate that the BTL cell has the superiorities of increasing the heating efficiency, decreasing the power consumption and reducing the RESET current from 0.67mA to 0.32mA. Therefore, the BTL cell will be appropriate for high performance PCRAM device with lower power consumption and lower RESET current.展开更多
The Fresnel approximation in phase screen model is discussed and the coherencefunction is derived for k】】k.The application condition for Rino’s results is obtained,and it is|▽R<sub>△N<sub>e</sub>...The Fresnel approximation in phase screen model is discussed and the coherencefunction is derived for k】】k.The application condition for Rino’s results is obtained,and it is|▽R<sub>△N<sub>e</sub></sub>|/R<sub>△n<sub>e</sub></sub>【【1.展开更多
We apply the derivative coupling model with ZM and ZM3 parameters to investigate the longitudinal response function in quasielastic electron scattering in the relativistic random phase approximation. The non-spectral ...We apply the derivative coupling model with ZM and ZM3 parameters to investigate the longitudinal response function in quasielastic electron scattering in the relativistic random phase approximation. The non-spectral method is chosen to describe the nucleon Green＇s function in a finite nucleus. Some remarks have been made in conclusion.展开更多
We are concerned with the susceptible-infective-removed （SIR） model with random transition rates on complete graphs Cn with n vertices. We assign independent and identically distributed （i.i.d.） copies of a positi...We are concerned with the susceptible-infective-removed （SIR） model with random transition rates on complete graphs Cn with n vertices. We assign independent and identically distributed （i.i.d.） copies of a positive random variable ξ on each vertex as the recovery rates and i.i.d, copies of a positive random variable ρ on each edge as the edge infection weights. We assume that a susceptible vertex is infected by an infective one at rate proportional to the edge weight on the edge connecting these two vertices while an infective vertex becomes removed with rate equals the recovery rate on it, then we show that the model performs the following phase transition when at t = 0 one vertex is infective and others are susceptible. There exists λc 〉 0 such that when λ 〈 λc, the proportion r∞ of vertices which have ever been infective converges to 0 weakly as n → ＋∞ while when λ 〉 λc, there exist c（λ） 〉 0 and b（λ） 〉 0 such that for each n ≥ 1 with probability p ≥ b（λ）, the proportion r∞ ≥ c（λ）. Furthermore, we prove that Ac is the inverse of the production of the mean of p and the mean of the inverse of ξ.展开更多
The configuration-bias-vaporization Monte Carlo simulation method developed by Yan et al . has been used to simulate the phase equilibria of AB random copolymers based on the close-packed Flory-Huggins lattice model. ...The configuration-bias-vaporization Monte Carlo simulation method developed by Yan et al . has been used to simulate the phase equilibria of AB random copolymers based on the close-packed Flory-Huggins lattice model. Random copolymers are represented as linear chains consisted of r A segment A and r B segment B with segment-segment attractive interaction energy parameters ε AA / kT=-1.0/T *, ε AB / kT=-0.8/T * and ε BB / kT=-0.6/T *. The phase diagrams of random copolymers with a chain length up to 200 segments are obtained. The corresponding critical points for different chain lengths with fixed chain composition are also calculated.展开更多
基金Supported by the Strategic Priority Research Program of the Chinese Academy of Sciences under Grant No XDA09020402the National Integrate Circuit Research Program of China under Grant No 2009ZX02023-003+1 种基金the National Natural Science Foundation of China under Grant Nos 61261160500,61376006,61401444 and 61504157the Science and Technology Council of Shanghai under Grant Nos 14DZ2294900,15DZ2270900 and 14ZR1447500
文摘An optimized device structure for reducing the RESET current of phase-change random access memory （PCRAM） with blade-type like （BTL） phase change layer is proposed. The electrical thermal analysis of the BTL cell and the blade heater contactor structure by three-dimensional finite element modeling are compared with each other during RESET operation. The simulation results show that the programming region of the phase change layer in the BTL cell is much smaller, and thermal electrical distributions of the BTL cell are more concentrated on the TiN/GST interface. The results indicate that the BTL cell has the superiorities of increasing the heating efficiency, decreasing the power consumption and reducing the RESET current from 0.67mA to 0.32mA. Therefore, the BTL cell will be appropriate for high performance PCRAM device with lower power consumption and lower RESET current.
文摘The Fresnel approximation in phase screen model is discussed and the coherencefunction is derived for k】】k.The application condition for Rino’s results is obtained,and it is|▽R<sub>△N<sub>e</sub></sub>|/R<sub>△n<sub>e</sub></sub>【【1.
基金Supported by National Basic Research Program of China (2009CB824800)National Natural Science Foundation of China (11103001)+1 种基金Hunan Provincial Natural Science Foundation of China (11JJ3006)Research Grants of Changsha University of Science and Technology,the Construct Program of the Key Discipline in Hunan Province and Aid Program for Science and Technology Innovative Research Team in Higher Educational Institute of Hunan Province
文摘We apply the derivative coupling model with ZM and ZM3 parameters to investigate the longitudinal response function in quasielastic electron scattering in the relativistic random phase approximation. The non-spectral method is chosen to describe the nucleon Green＇s function in a finite nucleus. Some remarks have been made in conclusion.
基金Acknowledgements The author is grateful to the reviewers. Their comments is a great help for him to improve this paper. In the original version, the author only proved that the main result holds under Assumption （7）. According to the reviewers＇ comments, he learned how to show that the main result holds under Assumption （1）. This work was supported by the National Natural Science Foundation of China （Grant No. 11501542） and the financial support from Beijing Jiaotong University （Grant No. KSRC16006536）.
文摘We are concerned with the susceptible-infective-removed （SIR） model with random transition rates on complete graphs Cn with n vertices. We assign independent and identically distributed （i.i.d.） copies of a positive random variable ξ on each vertex as the recovery rates and i.i.d, copies of a positive random variable ρ on each edge as the edge infection weights. We assume that a susceptible vertex is infected by an infective one at rate proportional to the edge weight on the edge connecting these two vertices while an infective vertex becomes removed with rate equals the recovery rate on it, then we show that the model performs the following phase transition when at t = 0 one vertex is infective and others are susceptible. There exists λc 〉 0 such that when λ 〈 λc, the proportion r∞ of vertices which have ever been infective converges to 0 weakly as n → ＋∞ while when λ 〉 λc, there exist c（λ） 〉 0 and b（λ） 〉 0 such that for each n ≥ 1 with probability p ≥ b（λ）, the proportion r∞ ≥ c（λ）. Furthermore, we prove that Ac is the inverse of the production of the mean of p and the mean of the inverse of ξ.
文摘The configuration-bias-vaporization Monte Carlo simulation method developed by Yan et al . has been used to simulate the phase equilibria of AB random copolymers based on the close-packed Flory-Huggins lattice model. Random copolymers are represented as linear chains consisted of r A segment A and r B segment B with segment-segment attractive interaction energy parameters ε AA / kT=-1.0/T *, ε AB / kT=-0.8/T * and ε BB / kT=-0.6/T *. The phase diagrams of random copolymers with a chain length up to 200 segments are obtained. The corresponding critical points for different chain lengths with fixed chain composition are also calculated.
