在实验中,他们先将两个原子制备到某种能量最低的基态:强局域被动态(strong local passive state),对其中任何一个原子进行任意局域操作都无法取出能量,且原子间有量子纠缠。然后他们对原子A与辅助原子C施加脉冲,打开它们之间的耦合,使辅助原子C 获得原子A的部分信息,并确保此操作不会改变原子B的能量。然后把原子C与原子B之间的耦合打开,这等价于把原子A的信息传递给B。在这一系列操作之后,我们就可以用局域操作从原子B中获得能量了。上述实验步骤只需37毫秒就可以完成,而能量从A传输到B原子所需要的时间需要一秒钟,远长于实验时间。此论文已被《物理评论快报》(PRL)接收。在此实验贴到预印本网站后过了8个月,另外一位学者基于IBM量子云平台,也独立实现了量子隐形传输能量的验证。
Michael A.Nielsen (迈克尔 A. 尼尔森)曾任澳大利亚联邦教授、圆周理论物理研究所高级研究员,曾在洛斯阿拉莫斯国家实验室担任访问职务,并曾在加利福尼亚理工学院担任托尔曼博士后研究员。
Isaac L.Chuang(艾萨克 L. 庄)现任麻省理工学院数据学习中心副主任,物理系和电气工程系教授,曾在斯坦福大学获得电气工程博士学位,赫兹基金会的研究员,同时还拥有麻省理工学院的物理学和电气工程学位。
本书译者
孙晓明 中国科学院计算技术研究所研究员。主要研究领域为算法与计算复杂性、量子计算等。曾获首批国家自然科学基金优秀青年基金资助,入选中组部首批万人计划青年拔尖人才,中国密码学会优秀青年奖、密码创新二等奖。目前担任中国计算机学会理论计算机科学专委会主任,全国量子计算与测量标准化技术委员会委员,还担任《软件学报》《计算机研究与发展》《中国科学:信息科学》《Information and Computation》《JCST》《FCS》等杂志编委或青年编委。 作为发起人负责整体翻译工作的推进与协调,并负责完成了第1章“简介与概述”和第3章“计算机科学简介”,以及附录的翻译。
图4 谷歌时间晶体实验示意图。(a):制造离散时间晶体的过程,将系统初态制备到二进制字符串态。通过数字量子模拟方法,用量子门电路模拟离散时间晶体的哈密顿量,并在结束时读取其Pauli-z算符的期望。(b):对于不同初态和失序取平均的离散时间晶体动力学。(c):热化系统的行为和多体局域化离散时间晶体行为的对比。(d):通过回声线路进行降噪后获得的无退相干影响的离散时间晶体动力学。(来源:谷歌离散时间晶体预印本Observation of Time-Crystalline Eigenstate Order on a Quantum Processor)
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