One-dimensional quantum emitters and photons for quantum technologies: 1D QED

用于量子技术的一维量子发射器和光子：1D QED

• 批准号: EP/N003381/1
• 负责人: Ruth Oulton
• 金额: $ 129.26万
• 依托单位: University of Bristol
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2016
• 资助国家: 英国
• 起止时间: 2016 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FN003381%2F1
• 关键词: dimensional; quantum; emitters; photons; technologies

Quantum technologies exploit the intrinsic quantum nature of particles such as photons and electrons. It has been known for some time that the ability to control the exact state of these particles, and to precisely control how they interact, will lead to unprecedented breakthroughs in a variety of technological applications. One of the immediate goals of quantum technologies is to exploit the fact that quantum particles can never be copied whilst retaining all of their information. Because the particle cannot be cloned, one may encode a cryptographic key in this way, as an eavesdropper would reveal their presence by changing the photon state as it is measured. Practical cryptographic "quantum key distribution", however, has limited information transfer rate by the fact that one needs to ensure that only one photon is transmitted per bit. To make sure that exactly one photon is generated, a "single photon source" from a quantum emitter such as an atom is required, or in our case, an "artificial atom", a quantum dot. We will fabricate single photon sources that output photons with very high efficiency into a fibre at a useful telecommunications wavelength (1300nm).The long-term goal of quantum technologies is to create a "universal quantum computer". This would use quantum particles as "quantum bits" that show the property of "superposition" (the ability to prepare a particle two states at once) and "entanglement" (sharing the superposition between several particles). Manipulating quantum bit interactions leads to a way of performing calculations with a complexity that speeds up exponentially with number of quantum bits. Preparing states for a quantum computer that will perform any calculation (a "universal" computer), however, is very challenging.Nevertheless, if one has a particular complex problem to solve, one may turn to quantum simulation instead. In this case, a calculation may be pre-programmed. It is known that by using photonic circuits (essentially a photon circuit consisting of the equivalent of mirrors and beamsplitters) one may perform a quantum simulation. A network of many channels is set up, and single photons input into chosen channels. However, an important requirement is that, again, controlled single photons must be available. The requirements are more stringent than for quantum communication. A second requirement is that each photon must be absolutely identical in bandwidth, wavelength and polarization - this is known as "indistinguishability". Indistinguishable photons input onto a beamsplitter undergo quantum interference that acts as a logic gate.Truly indistinguishable single photons are extremely difficult to create. Nevertheless, a great deal of progress has been made in precisely controlling single photons using single atoms trapped in an optical cavity. However, atoms emit photons slowly, and collecting all photons is difficult. The rate at which single photons can be generated is presently still too low and the experimental setup involved very large, and unsuitable for anywhere except a laboratory.However, quantum dots have very similar properties to atoms. These emit light far faster than atoms (at a rate of 1 billion photons per second) and may also be incorporated into semiconductor "cavities". In this proposal, I will show that one may collect the light extremely efficiently using similar optical fibre technology to that used in telecommunication networks. By doing this, I will provide single photon sources to quantum communication networks and quantum simulation devices. This will lead to absolutely secure communications, and the ability to calculate properties of novel materials or complex molecules to help design new drugs, and factorize large prime numbers used in cryptography.

量子技术利用光子和电子等粒子的内在量子性质。一段时间以来，人们已经知道，控制这些粒子的确切状态以及精确控制它们如何相互作用的能力，将导致各种技术应用的前所未有的突破。量子技术的直接目标之一是利用量子粒子永远无法复制同时保留其所有信息的事实。因为粒子不能被克隆，所以可以用这种方式编码密钥，因为窃听者会通过改变测量的光子状态来揭示它们的存在。然而，实际的密码学“量子密钥分配”由于需要确保每比特仅传输一个光子的事实而具有有限的信息传输速率。为了确保只产生一个光子，需要一个来自量子发射器（如原子）的“单光子源”，或者在我们的情况下，一个“人造原子”，一个量子点。我们将制造单光子源，以非常高的效率将光子输出到有用的电信波长（1300 nm）的光纤中。量子技术的长期目标是创建“通用量子计算机”。这将使用量子粒子作为“量子比特”，表现出“叠加”（一次制备粒子两种状态的能力）和“纠缠”（在几个粒子之间共享叠加）的特性。操纵量子比特相互作用导致了一种执行计算的方式，其复杂性随着量子比特的数量呈指数级增长。然而，为一台可以执行任何计算的量子计算机（一台“通用”计算机）准备状态是非常具有挑战性的。然而，如果有一个特别复杂的问题需要解决，人们可以转向量子模拟。在这种情况下，可以对计算进行预编程。众所周知，通过使用光子电路（本质上是由等效的反射镜和分束器组成的光子电路），可以执行量子模拟。建立一个多通道的网络，并将单个光子输入到选定的通道中。然而，一个重要的要求是，受控的单光子必须是可用的。其要求比量子通信更严格。第二个要求是每个光子必须在带宽，波长和偏振方面完全相同-这被称为“不可分割性”。输入到分束器的不可分辨光子经历量子干涉，量子干涉充当逻辑门。真正不可分辨的单光子是极难产生的。尽管如此，在利用囚禁在光学腔中的单原子精确控制单光子方面已经取得了很大进展。然而，原子缓慢地发射光子，并且收集所有光子是困难的。目前，单光子的产生率还很低，实验装置也很大，除了实验室外，不适合在任何地方进行。然而，量子点具有与原子非常相似的性质。它们发射光的速度远远快于原子（每秒10亿个光子），也可能被纳入半导体“空腔”。在这个提议中，我将展示人们可以使用类似于电信网络中使用的光纤技术来非常有效地收集光。通过这样做，我将为量子通信网络和量子模拟设备提供单光子源。这将导致绝对安全的通信，以及计算新材料或复杂分子的特性以帮助设计新药的能力，以及对密码学中使用的大素数进行因子分解的能力。

项目成果

Model for confined Tamm plasmon devices

• DOI: 10.1364/josab.36.000125
• 发表时间: 2019-01-01
• 期刊: JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
• 影响因子: 1.9
• 作者: Adams, Mike;Cemlyn, Ben;Oulton, Ruth
• 通讯作者: Oulton, Ruth

On the impact of realistic point sources in spatial mode demultiplexing super resolution imaging

空间模式解复用超分辨率成像中真实点源的影响

• DOI: 10.1088/2058-9565/aca0b7
• 发表时间: 2023
• 期刊: Quantum Science and Technology
• 影响因子: 6.7
• 作者: Greenwood A

High extraction efficiency source of photon pairs based on a quantum dot embedded in a broadband micropillar cavity

基于嵌入宽带微柱腔中的量子点的高提取效率光子对源

• DOI: 10.48550/arxiv.2112.13074
• 发表时间: 2021
• 作者: Ginés L

A model for confined Tamm plasmon devices

受限Tamm等离子体激元装置的模型

• DOI: 10.48550/arxiv.1809.07512
• 发表时间: 2018
• 作者: Adams M

Optimal simultaneous measurements of incompatible observables of a single photon

• DOI: 10.1364/optica.6.000257
• 发表时间: 2018-08
• 期刊: Optica
• 影响因子: 10.4
• 作者: A. Dada;W. McCutcheon;E. Andersson;J. Crickmore;I. Puthoor;B. Gerardot;A. McMillan;J. Rarity;R. Oulton