Photonic Quantum Control Technologies

20世纪初量子力学的引入使我们对自然的理解发生了根本性的变化。虽然经典物理支配着我们周围宏观世界中最熟悉的元素，但电子、原子和分子的微观行为是量子力学的领域。量子力学表现出许多独特的特征--不确定性、叠加和纠缠--这些在经典世界中几乎没有类似之处。我们现在知道，这些量子特征可以用来开发新的量子技术，这是经典物理学无法想象的。为了建立量子技术，我们必须开发操纵这些量子系统的方法。这项提议的目的是研究通过使用激光脉冲来控制量子系统，然后利用这些可控的量子系统来开发新技术。 基本上，所有的原子和分子物理都受电磁场的支配，我们将利用这一事实来控制具有强非共振激光场的量子系统。我们将对多原子分子中的光反应进行控制，并改变其分支比，这是努力控制更大系统的重要第一步。我们将利用激光控制和分子独特的能级结构来开发光量子存储器，这是未来量子通信和计算必不可少的光子存储设备。我们建议把块状金刚石的声子态作为一个“量子工作台”来研究。该系统提供了室温固态量子处理的激发潜力，并使类似于分子的控制方法成为可能。量子技术都依赖于维持系统的一致性。我们将研究这些系统中的相干损失，以努力减少其影响，并将其用作产生量子随机数的资源，这是未来通信安全的重要组成部分。

The introduction of quantum mechanics early in the 20th century led to a radical change in our understanding of Nature. While classical physics governs the most familiar elements of the macroscopic world around us, the microscopic behaviour of electrons, atoms, and molecules is the realm of quantum mechanics. Quantum mechanics exhibits a host of unique features - uncertainty, superposition, and entanglement - that have little analogue in the classical world. We now understand that these quantum features can be utilized to develop new Quantum Technologies, impossible to imagine with classical physics. In order to build Quantum Technologies we must develop methods for manipulating these quantum systems. The purpose of this proposal is to investigate the control of quantum systems through the use of laser pulses and then to use these controllable quantum systems to develop new technologies. Essentially all of atomic & molecular physics is governed by electromagnetic fields and we will use this fact to control quantum systems with intense nonresonant laser fields. We will apply control to a photo-reaction in a polyatomic molecule and alter its branching ratio, an important first step in efforts to control larger systems. We will utilize laser control and the unique level structure of molecules to develop optical quantum memories, a photon storage device essential for future quantum communication and computation. We propose to investigate the phonon states of bulk diamond as a `quantum workbench'. This system offers the exciting potential of room-temperature solid-state quantum processing and enables similar control approaches as in molecules. Quantum Technologies all rely on system coherence being maintained. We will study loss of coherence in these systems in an effort to both reduce its effects and to use it as a resource for quantum random number generation, an important part of future communications security.