Recent theory and experiments show that artificial magnetic skyrmions can be stabilized at room temperature without the need for the external magnetic field,casting strong potentials for the device applications.In thi...Recent theory and experiments show that artificial magnetic skyrmions can be stabilized at room temperature without the need for the external magnetic field,casting strong potentials for the device applications.In this work,we study the electric field manipulation of artificial magnetic skyrmions imprinted by Co disks on CoPt multilayers utilizing the micromagnetic simulations.We find that the reversible annihilation and creation of skyrmions can be realized with the electric field via the strain mediated magnetoelastic coupling.In addition,we also demonstrate controllable manipulation of individual skyrmion,which opens a new platform for constructing magnetic field-free and low-energy dissipation skyrmion based media.展开更多
Scanning tunneling microscopy is a powerful tool to build artificial atomic structures that do not exist in nature but possess exotic properties.In this study,we constructed Lieb lattices with different lattice consta...Scanning tunneling microscopy is a powerful tool to build artificial atomic structures that do not exist in nature but possess exotic properties.In this study,we constructed Lieb lattices with different lattice constants by real atoms,i.e.,Fe atoms on Ag(111),and probed their electronic properties.We obtain a surprising long-range effective electron wavefunction overlap between Fe adatoms as it exhibits a 1/r;dependence with the interatomic distance r instead of the theoretically predicted exponential one.Combining control experiments,tight-binding modeling,and Green’s function calculations,we attribute the observed long-range overlap to being enabled by the surface state.Our findings enrich the understanding of the electron wavefunction overlap and provide a convenient platform to design and explore artificial structures and future devices with real atoms.展开更多
Due to the capacity of thermal storage,electric water heater(EWH)is one of the best candidates for demand response programs.However,few attentions are given to the modeling and optimization of EWHs with thermostatical...Due to the capacity of thermal storage,electric water heater(EWH)is one of the best candidates for demand response programs.However,few attentions are given to the modeling and optimization of EWHs with thermostatically-controlled automatic water mixer(TCAWM).In this paper,differential thermodynamic model is established for EWHs with TCAWM and a piecewise linear approximation method is performed for the nonlinear thermodynamic model.The multi-objective optimization model is established by introducing an index reflecting the comfort degree of users,so that the optimal energy usage of the EWH can be obtained by mixed integer linear programming.Testing examples verify the effectiveness of the proposed method.展开更多
As a kind of important demand side resource,the thermostatically controlled loads(TCLs)play an important role in the peak load shifting and load balancing programs.This paper establishes a state-queuing(SQ)model for t...As a kind of important demand side resource,the thermostatically controlled loads(TCLs)play an important role in the peak load shifting and load balancing programs.This paper establishes a state-queuing(SQ)model for the large-scale TCLs,and estimates the system states based on the Kalman-filtering.Based on state estimation,the control strategy,whose parameters are optimized by the genetic algorithm(GA),is designed to damp the power fluctuation of the TCLs.Finally,the effectiveness of the proposed method is verified.展开更多
基金Project supported by the National Key R&D Program of China(Grant Nos.2021YFB3502400 and 2022YFA1403601)the National Natural Science Foundation of China(Grant Nos.12274204,12274203,51831005,52172270,11974165,92165103,51971110,12004329,and 12241402).
文摘Recent theory and experiments show that artificial magnetic skyrmions can be stabilized at room temperature without the need for the external magnetic field,casting strong potentials for the device applications.In this work,we study the electric field manipulation of artificial magnetic skyrmions imprinted by Co disks on CoPt multilayers utilizing the micromagnetic simulations.We find that the reversible annihilation and creation of skyrmions can be realized with the electric field via the strain mediated magnetoelastic coupling.In addition,we also demonstrate controllable manipulation of individual skyrmion,which opens a new platform for constructing magnetic field-free and low-energy dissipation skyrmion based media.
基金supported by the National Key R&D Program of China(Grant Nos.2017YFA0303202 and 2018YFA0306004)the National Natural Science Foundation of China(Grant Nos.11974165,92165103,51971110,and 11734006)+1 种基金the China Postdoctoral Science Foundation(Grant No.2019M651766)the Natural Science Foundation of Jiangsu Province(Grant No.BK20190057)。
文摘Scanning tunneling microscopy is a powerful tool to build artificial atomic structures that do not exist in nature but possess exotic properties.In this study,we constructed Lieb lattices with different lattice constants by real atoms,i.e.,Fe atoms on Ag(111),and probed their electronic properties.We obtain a surprising long-range effective electron wavefunction overlap between Fe adatoms as it exhibits a 1/r;dependence with the interatomic distance r instead of the theoretically predicted exponential one.Combining control experiments,tight-binding modeling,and Green’s function calculations,we attribute the observed long-range overlap to being enabled by the surface state.Our findings enrich the understanding of the electron wavefunction overlap and provide a convenient platform to design and explore artificial structures and future devices with real atoms.
基金supported by National Natural Science Foundation of China(No.51707099)Natural Science Fund for Colleges and Universities of Jiangsu Province(No.16KJB470009)China Postdoctoral Science Foundation(No.2017M611859).
文摘Due to the capacity of thermal storage,electric water heater(EWH)is one of the best candidates for demand response programs.However,few attentions are given to the modeling and optimization of EWHs with thermostatically-controlled automatic water mixer(TCAWM).In this paper,differential thermodynamic model is established for EWHs with TCAWM and a piecewise linear approximation method is performed for the nonlinear thermodynamic model.The multi-objective optimization model is established by introducing an index reflecting the comfort degree of users,so that the optimal energy usage of the EWH can be obtained by mixed integer linear programming.Testing examples verify the effectiveness of the proposed method.
基金This work was partially supported by National Natural Science Foundation of China(51707099)University Science Research Project of Jiangsu Province(16KJB470009)China Postdoctoral Science Foundation(2017M611859).
文摘As a kind of important demand side resource,the thermostatically controlled loads(TCLs)play an important role in the peak load shifting and load balancing programs.This paper establishes a state-queuing(SQ)model for the large-scale TCLs,and estimates the system states based on the Kalman-filtering.Based on state estimation,the control strategy,whose parameters are optimized by the genetic algorithm(GA),is designed to damp the power fluctuation of the TCLs.Finally,the effectiveness of the proposed method is verified.