Electron spins confined in semiconductor quantum dots(QDs)are one of potential candidates for physical implementation of scalable quantum information processing technologies.Tunnel coupling based inter exchange intera...Electron spins confined in semiconductor quantum dots(QDs)are one of potential candidates for physical implementation of scalable quantum information processing technologies.Tunnel coupling based inter exchange interaction between QDs is crucial in achieving single-qubit manipulation,two-qubit gate,quantum communication and quantum simulation.This review first provides a theoretical perspective that surveys a general framework,including the Helter−London approach,the Hund−Mulliken approach,and the Hubbard model,to describe the inter exchange interactions between semiconductor quantum dots.An electrical method to control the inter exchange interaction in a realistic device is proposed as well.Then the significant achievements of inter exchange interaction in manipulating single qubits,achieving two-qubit gates,performing quantum communication and quantum simulation are reviewed.The last part is a summary of this review.展开更多
We report on the transport study of a double quantum dot(DQD)device made from a freestanding,single crystalline InSb nanosheet.The freestanding nanosheet is grown by molecular beam epitaxy and the DQD is defined by th...We report on the transport study of a double quantum dot(DQD)device made from a freestanding,single crystalline InSb nanosheet.The freestanding nanosheet is grown by molecular beam epitaxy and the DQD is defined by the top gate technique.Through the transport measurements,we demonstrate how a single quantum dot(QD)and a DQD can be defined in an InSb nanosheet by tuning voltages applied to the top gates.We also measure the charge stability diagrams of the DQD and show that the charge states and the inter-dot coupling between the two individual QDs in the DQD can be efficiently regulated by the top gates.Numerical simulations for the potential profile and charge density distribution in the DQD have been performed and the results support the experimental findings and provide a better understanding of fabrication and transport characteristics of the DQD in the InSb nanosheet.The achieved DQD in the two-dimensional InSb nanosheet possesses pronounced benefits in lateral scaling and can thus serve as a new building block for the developments of quantum computation and quantum simulation technologies.展开更多
基金funded by National Natural Science Foundation of China,(Grant Nos.11974030 and 92165208)。
文摘Electron spins confined in semiconductor quantum dots(QDs)are one of potential candidates for physical implementation of scalable quantum information processing technologies.Tunnel coupling based inter exchange interaction between QDs is crucial in achieving single-qubit manipulation,two-qubit gate,quantum communication and quantum simulation.This review first provides a theoretical perspective that surveys a general framework,including the Helter−London approach,the Hund−Mulliken approach,and the Hubbard model,to describe the inter exchange interactions between semiconductor quantum dots.An electrical method to control the inter exchange interaction in a realistic device is proposed as well.Then the significant achievements of inter exchange interaction in manipulating single qubits,achieving two-qubit gates,performing quantum communication and quantum simulation are reviewed.The last part is a summary of this review.
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2017YFA0303304,2016YFA0300601,2017YFA0204901,2016YFA0300802)the National Natural Science Foundation of China(Grant Nos.91221202,91421303,11874071,11974030,and 61974138)+3 种基金the Beijing Academy of Quantum Information Sciences(Grant No.Y18G22)the Key-Area Research and Development Program of Guangdong Province,China(Grant No.2020B0303060001)the Beijing Natural Science Foundation,China(Grant Nos.1202010 and 1192017)the support from Youth Innovation Promotion Association,Chinese Academy of Sciences(Grant No.2017156)。
文摘We report on the transport study of a double quantum dot(DQD)device made from a freestanding,single crystalline InSb nanosheet.The freestanding nanosheet is grown by molecular beam epitaxy and the DQD is defined by the top gate technique.Through the transport measurements,we demonstrate how a single quantum dot(QD)and a DQD can be defined in an InSb nanosheet by tuning voltages applied to the top gates.We also measure the charge stability diagrams of the DQD and show that the charge states and the inter-dot coupling between the two individual QDs in the DQD can be efficiently regulated by the top gates.Numerical simulations for the potential profile and charge density distribution in the DQD have been performed and the results support the experimental findings and provide a better understanding of fabrication and transport characteristics of the DQD in the InSb nanosheet.The achieved DQD in the two-dimensional InSb nanosheet possesses pronounced benefits in lateral scaling and can thus serve as a new building block for the developments of quantum computation and quantum simulation technologies.
