Towards Real Applications in Broadband Quantum Memories

走向宽带量子存储器的实际应用

基本信息

批准号：
EP/J000051/1
负责人：
Ian Walmsley
金额：
$ 112.92万
依托单位：
University of Oxford
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2012
资助国家：
英国
起止时间：
2012 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=EP%2FJ000051%2F1
关键词：
Towards Real Applications Broadband Quantum

项目摘要

Imagine a banknote that cannot be forged, because the serial number is scrambled every time someone tries to read it. But if you are the banker, you can read it. Sounds like Harry Potter? Imagine a computer that predicts how drugs will behave by simulating all possible chemical reactions at once! This is not an idea from Phillip Pullman's fantasy of parallel universes. Real technologies like this are just around the corner.This is the fascinating, counter-intuitive world of quantum physics. Huge advances in communications and computing technology over the last several decades have made this the information age and changed the way people live and interact even more drastically than did the industrial revolution. These advances have piggy-backed on the development of devices such as semiconductor transistors and lasers, devices which wouldn't be possible without the weird properties of quantum physics.But although modern computers have far-outstripped the early technology of punch cards and vacuum tube valves, at an underlying conceptual level, they still use exactly the same type of information - strings of 0s and 1s called bits. Quantum physics will allow us go far beyond this into the strange world of quantum information, where the "quantum bits" can be both 0 and 1 simultaneously! Computers that could work with this sort of information would be exponentially faster at performing difficult simulations or cracking codes. And communicating using quantum information can be made "eavesdropper proof" - perfectly secure.Over the past ten years, an enormous research effort has brought these extraordinary technologies from abstract ideas to small-scale experiments. One of the most promising ways to build a quantum computer is based on single particles of light, called photons, which can be sent over long distances in optical fibres and manipulated with ordinary lenses and mirrors. But like normal computers, quantum computers need memories to be able to synchronise different parts of a computation by storing the quantum information until it is needed. So to build a photonic quantum computer, we also need to have a quantum memory that can store single photons. What makes this difficult is that these special memories need to be able to store the fragile quantum information without destroying or even "looking" at it (measuring it).In this project, we will develop a quantum memory for photons which can store short pulses for long times with high efficiency and very low noise. To do this, we will use a "Raman memory", an approach pioneered in our group which uses a strong laser pulse to cause the photon to be absorbed by a sample of atoms which is normally transparent. Because the absorption is created by the strong laser (which is not absorbed), there is no noise from excited atoms, and the atoms don't need to be specially prepared by cooling them or trapping them.The simplicity of our design will allow us to build the first practically feasible memory, which would even potentially be capable of operating in isolated, harsh environments, such as on the ocean floor. This will also allow us to perform novel photonics experiments which are too complex to operate without the memory. We will also develop a miniaturized memory that could be mass-produced and integrated with existing telecoms fibres. Such a device will do for quantum photonics what the transistor did for conventional electronics.Quantum memories will open the way to a new era of quantum enabled devices, with super-fast computers, perfectly secure communications and ultra-precise measurements. Our research is the key to bringing these truly magical technologies to life.

想象一张无法伪造的钞票，因为每次有人试图读取它时，序列号都会被打乱。但如果你是银行家，你可以阅读它。听起来像哈利波特？想象一下，一台计算机通过同时模拟所有可能的化学反应来预测药物的行为！这并不是菲利普·普尔曼的平行宇宙幻想中的想法。像这样的真正技术指日可待。这就是令人着迷、反直觉的量子物理世界。过去几十年来，通信和计算技术的巨大进步使我们进入了信息时代，并比工业革命更彻底地改变了人们的生活和互动方式。这些进步带动了半导体晶体管和激光器等设备的发展，如果没有量子物理学的奇怪特性，这些设备就不可能实现。但是，尽管现代计算机已经远远超过了打孔卡和真空管的早期技术阀门，在底层概念层面上，它们仍然使用完全相同类型的信息 - 称为位的 0 和 1 字符串。量子物理学将让我们远远超出这个范围，进入量子信息的奇怪世界，其中“量子比特”可以同时为 0 和 1！能够处理此类信息的计算机在执行困难的模拟或破解代码时速度会呈指数级增长。使用量子信息进行通信可以做到“防窃听”——完全安全。在过去的十年里，大量的研究工作使这些非凡的技术从抽象的想法变成了小规模的实验。构建量子计算机最有前途的方法之一是基于称为光子的单个光粒子，它可以通过光纤长距离发送，并用普通透镜和镜子进行操纵。但与普通计算机一样，量子计算机需要存储器，以便能够通过存储量子信息直到需要时来同步计算的不同部分。因此，要构建光子量子计算机，我们还需要有一个可以存储单个光子的量子存储器。让这一切变得困难的是，这些特殊的存储器需要能够存储脆弱的量子信息，而不破坏甚至不“查看”它（测量它）。在这个项目中，我们将开发一种可以存储短脉冲的光子量子存储器长时间运行，效率高，噪音极低。为此，我们将使用“拉曼存储器”，这是我们小组首创的一种方法，它使用强激光脉冲使光子被通常透明的原子样本吸收。因为吸收是由强激光（未被吸收）产生的，所以没有来自激发原子的噪音，并且原子不需要通过冷却或捕获它们来进行特殊准备。我们设计的简单性将使我们能够构建第一个实际可行的存储器，它甚至有可能能够在孤立的恶劣环境中运行，例如在海底。这也将使我们能够进行新颖的光子学实验，这些实验太复杂，没有内存就无法操作。我们还将开发一种可以大规模生产并与现有电信光纤集成的小型化存储器。这种设备对于量子光子学的作用就像晶体管对于传统电子学的作用一样。量子存储器将为量子设备的新时代开辟道路，具有超高速计算机、完全安全的通信和超精确测量。我们的研究是将这些真正神奇的技术变为现实的关键。

项目成果

期刊论文数量（9）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Direct observation of sub-binomial light

直接观察亚二项式光

DOI：
10.1103/physrevlett.110.173602
发表时间：
2013-02-01
期刊：
2013 Conference on Lasers & Electro-Optics Europe & International Quantum Electronics Conference CLEO EUROPE/IQEC
影响因子：
0
作者：
T. Bartley;G. Donati;Xian;A. Datta;M. Barbieri;I. Walmsley
通讯作者：
I. Walmsley

High-fidelity polarization storage in a gigahertz bandwidth quantum memory

DOI：
10.1088/0953-4075/45/12/124008
发表时间：
2011-12-05
期刊：
Journal of Physics B: Atomic, Molecular and Optical Physics
影响因子：
0
作者：
D. Engl;P. Michelberger;T. Champion;K. Reim;K. Reim;K. C. Lee;M. Sprague;X. Jin;X. Jin;N. Langford;N. Langford;W. Kolthammer;J. Nunn;I. Walmsley
通讯作者：
I. Walmsley

Direct observation of sub-binomial light

直接观察亚二项式光