An approximate artificial boundary condition based on a boundary integral equa- tion is designed for the vortex movements. Point vortex and cloud in cell methods are used in numerical simulation of vortex motions. The...An approximate artificial boundary condition based on a boundary integral equa- tion is designed for the vortex movements. Point vortex and cloud in cell methods are used in numerical simulation of vortex motions. The numerical experiments show that the ap- proximate artificial boundary condition is useful and su?ciently accurate in hydrodynamics.展开更多
Confined low dimensional charges with high density such as two-dimensional electron gas(2 DEG)at interfaces and charged domain walls in ferroelectrics show great potential to serve as functional elements in future nan...Confined low dimensional charges with high density such as two-dimensional electron gas(2 DEG)at interfaces and charged domain walls in ferroelectrics show great potential to serve as functional elements in future nanoelectronics.However,stabilization and control of low dimensional charges is challenging,as they are usually subject to enormous depolarization fields.Here,we demonstrate a method to fabricate tunable charged interfaces with~77°,86°and 94°head-to-head polarization configurations in multiferroic Bi Fe O_(3) thin films by grain boundary engineering.The adjacent grains are cohesively bonded and the boundary is about 1 nm in width and devoid of any amorphous region.Remarkably,the polarization remains almost unchanged near the grain boundaries,indicating the polarization charges are well compensated,i.e.,there should be two-dimensional charge gas confined at grain boundaries.Adjusting the tilt angle of the grain boundaries enables tuning the angle of polarization configurations from 71°to 109°,which in turn allows the control of charge density at the grain boundaries.This general and feasible method opens new doors for the application of charged interfaces in next generation nanoelectronics.展开更多
文摘An approximate artificial boundary condition based on a boundary integral equa- tion is designed for the vortex movements. Point vortex and cloud in cell methods are used in numerical simulation of vortex motions. The numerical experiments show that the ap- proximate artificial boundary condition is useful and su?ciently accurate in hydrodynamics.
基金supported by the National Basic Research Program of China(2016YFA0300804)the National Natural Science Foundation of China(51672007 and 11974023)+6 种基金Key Area R&D Program of Guangdong Province(2018B010109009)the Key R&D Program of Guangdong Province(2018B030327001)National Equipment Program of China(ZDYZ2015-1)the‘‘2011 Program”Peking-Tsinghua-IOP Collaborative Innovation Centre for Quantum Mattersupported by the National Basic Research Program of China(2016YFA0301004)the National Natural Science Foundation of China(51872155,52025024)the Beijing Advanced Innovation Center for Future Chip(ICFC)。
文摘Confined low dimensional charges with high density such as two-dimensional electron gas(2 DEG)at interfaces and charged domain walls in ferroelectrics show great potential to serve as functional elements in future nanoelectronics.However,stabilization and control of low dimensional charges is challenging,as they are usually subject to enormous depolarization fields.Here,we demonstrate a method to fabricate tunable charged interfaces with~77°,86°and 94°head-to-head polarization configurations in multiferroic Bi Fe O_(3) thin films by grain boundary engineering.The adjacent grains are cohesively bonded and the boundary is about 1 nm in width and devoid of any amorphous region.Remarkably,the polarization remains almost unchanged near the grain boundaries,indicating the polarization charges are well compensated,i.e.,there should be two-dimensional charge gas confined at grain boundaries.Adjusting the tilt angle of the grain boundaries enables tuning the angle of polarization configurations from 71°to 109°,which in turn allows the control of charge density at the grain boundaries.This general and feasible method opens new doors for the application of charged interfaces in next generation nanoelectronics.
