非掺杂砷化镓量子点自旋量子比特的制备和电荷噪声研究

项目名称： 非掺杂砷化镓量子点自旋量子比特的制备和电荷噪声研究

项目编号： No.61306150

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 无线电电子学、电信技术

项目作者： 李海欧

作者单位： 中国科学技术大学

项目金额： 27万元

中文摘要： 半导体砷化镓门型量子点一直是固态量子信息最前沿的研究领域，在电子自旋量子比特的制备、测量和操控等方面取得了一系列重大研究成果。然而，传统的砷化镓量子点是基于掺杂的砷化镓铝异质结中的二维电子气上形成的。由于掺杂不可避免的削弱电子电荷和自旋的稳定性，从而增加了量子比特受到掺杂电子电荷噪声的影响，缩短了量子比特的弛豫时间，加快了量子比特的的退相干过程。基于解决上述问题为核心研究目标，本项目将采用非掺杂砷化镓异质结进行新型双层结构量子点器件的加工，并对量子点中电子电荷和自旋状态进行测量和控制以及非掺杂所减小的电荷噪声影响，研究非掺杂影响自旋量子比特弛豫时间的机理，探究非掺杂对电子自旋量子比特退相干过程的影响，实现单电子自旋量子比特的制备、测量和操控。新型量子点器件是继承传统量子点器件可集成性等优势的同时，又具有高迁移率、强稳定性的增强型量子点研究体系，为推动固态量子计算机的应用化进程开辟新的道路。

中文关键词： 量子点；砷化镓；量子比特；量子逻辑门；

英文摘要： Gate-defined quantum dots based on GaAs/AlGaAs heterojunction have been the most cutting-edge research field of solid-state quantum information, and made a series of significant research in the experimental study of the spin qubits preparation,measurement and manipulation. However, the the traditional GaAs quantum dots are formed based on the two-dimensional electron gas in a doped GaAs/GaAlAs heterojunction. Doping will inevitably weaken the stability of the electron charge and spin, and increasing the impact of the doped electron charge noise and shorten the coherence time for spin qubits. Based on solving the above problems as the core research objectives,the project will produce the new two-tier structure of quantum dot devices using the undoped GaAs/AlGaAs heterojunction, and focus on the electron charge and spin state measurements and control.We will systematically study how to reduce noise and study the electron spin qubits decoherence characteristics,qubit preparation, measurements and manipulation. Novel quantum dot devices will not only inherit the advantages of traditional quantum dot devices, but also is a very good enhanced mode quantum dots system which has the high mobility and the strong stability. These basis will advance the solid-state quantum information research and open a new path of devel

英文关键词： quantum dot；GaAs；qubits；quantum logic gate；