题目: Multiple QuantumDot SpinQubits

报告人：Prof. SeigoTarucha,

               Department of Applied Physics, the University of Tokyo, Japan

摘要：

To date various techniques of implementingspin qubits and entangling gates have been developed with quantum dos (QDs). The necessary step for further scaling up the qubit system is to increase the number of QDs with well-controlled charge statesfor making multiplequbitsand improve the fidelity of the qubit gates. I will first review spin-1/2 qubit gates with triple or quadruple GaAs QDsfor operating three or four qubits andlocal and non-local entangling gates as well.Secondly Iwill discuss improvement of fidelity of qubit gates and influence from environment noise on quantum dephasing. I show that the fidelity is significantly increased by decreasing the data acquisition time. The fast measurement is useful to suppress the influence from slowly fluctuating nuclear spin environment.In addition I will compare the dephasing between GaAs QDs and Si QDs and discuss the large difference of noise environment.

简介：

SeigoTaruchawas born in Ehime in 1953.received the B. E. and M. S. degrees in appliedphysics from the University of Tokyo in 1976 and 1978, respectively. He joined NTT Basic Research Laboratories in1978 and received the Ph. D degree in applied physics from the University of Tokyo in 1986. In 1998 he moved to theUniversity of Tokyo as a professor in the Department ofPhysics(1998-2005) and then to the Department of Applied Physics (2005-present). Since 2011 he has been concurrently serving as a group director in Center for Emergent Matter Science, Riken.He has also been a director of Cryogenic Center in the Tokyo University since 2015. He was a guest scientist in Max-Planck-Institute (Stuttgart) from Jul. 1986 to Nov. 1987 and in Delft University Jul. to Oct. in 1995. He is currently working onquantum transport and correlation effects in semiconductor nanostructures andspin-based quantum computing with quantum dots.He was awarded Nishina award, National medal with purple ribbon , and Leo Esaki Award.

时间：2016年11月3日(星期四)上午10:00

地点：中科院物理研究所D楼211会议室

邀请人：许秀来研究员 （Tel：82649820）

联系人：金奎娟研究员 （Tel：82648099）

主办单位：中国科学院光物理重点实验室