Photon Temporal Modes as a Quantum Information Resource

该项目旨在开发一种利用光的光子对量子信息进行编码的新方法。在量子信息网络中，光子在网络节点之间传输量子信息，而量子信息网络的目的是以经典物理技术无法实现的方式存储、传输和处理信息。单光子的特征是它们的颜色(频率)、偏振方向、空间光束分布和时间形状。直到最近，光子的时间形状才被认为是编码量子信息的一种未得到充分利用的资源。PI将开发以单光子波包的时间形状对量子信息进行编码的方法，并演示处理此类编码信息的方法。这项研究有可能通过提高以与光纤网络兼容的方式在单个光子中存储更大量信息的能力来推动量子信息科学的发展。这项研究将影响包括量子计算在内的不断增长的量子信息技术领域，并提供将科学教育与研究相结合的绝佳机会。这项研究建立在PI最近成功展示了至关重要的信息处理设备-量子脉冲门-能够根据光脉冲的时间形状对其进行分类(和路由)的基础上。这项研究的目的是开发一套完整的概念和实用工具，以使用时间(波包)光模式执行量子信息操作。时间模式(TM)形成了占据时间-频率(相位)空间的相同区域的一组离散的场正交脉冲形状。研究人员最近通过实验演示了他们提出的分离(排序)时间模式的方法，该方法使用了一种新的光学频率转换形式。与基本上是两态系统的极化不同，时间模式基础提供了多能级量子逻辑(QUDITS)的可能性。要使TMS发挥其作为量子信息科学工具的潜力，需要证明具有时间模式的QIS所需的所有量子资源和操作都是可用的。具体地说，研究人员将致力于证明：1)TM纠缠光子的来源，2)TM基量子态层析，3)QPG器件本身的量子过程层析，以及4)在场正交TM中相干和高效地操纵光，以实现单光子量子逻辑门。控制量子系统的状态在科学和信息技术、计量学、量子化学和纳米力学中引起了广泛的兴趣。光学技术和基于量子光学的信息科学提供了将研究与科学教育相结合的绝佳机会。该协会于2010年在俄勒冈大学共同创立了科学素养计划(SLP)，并担任联席主任，目前是顾问委员会成员。SLP为许多担任科学素养课程联合导师的研究生和本科生提供辅导机会，这些课程影响了该大学数千名学生。在这个项目中，PI将教授和指导SLP课程的讲师，该课程向非理科专业的学生介绍量子信息科学，使用基于探究的学习技术来吸引学生。国际和平协会已经为这门课程出版了一本受欢迎的书，量子物理：每个人都需要知道的东西(牛津，2017)，并将继续使用这本书中的材料来促进教育，作为这个项目的一部分。一位从事量子信息科学研究的博士生担任联合导师，计划课程学习目标，准备和展示几堂课，写作业和考试问题，并在课堂上促进小组问题解决活动。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This project aims to develop a new approach for using photons of light to encode quantum information. In a quantum information network, whose purpose is to store, transmit and manipulate information in ways not possible using classical physics techniques, photons transfer quantum information between network nodes. Single photons are characterized by their color (frequency), polarization orientation, spatial beam profile, and temporal shape. Only recently has the temporal shape of photons been recognized as an underutilized resource for encoding quantum information. The PI will develop methods to encode quantum information in the temporal shape of single-photon wave packets, and to demonstrate means for manipulating such encoded information. This research has the potential to advance quantum information science by improving the ability to store larger amounts of information in single photons in a manner that is compatible with optical-fiber networks. The research will impact the growing field of quantum information technology, including quantum computing, and offers excellent opportunities to integrate science education with research. The research builds on the PI's recent successful demonstration of the crucially needed information-processing device - the quantum pulse gate - that is capable of sorting (and routing) optical pulses according to their temporal shape. The research aims to develop the complete set of conceptual and practical tools needed for performing quantum information operations using temporal (wave-packet) modes of light. Temporal modes (TMs) form a discrete set of field-orthogonal pulse shapes that occupy the same region of time-frequency (phase) space. The researchers recently experimentally demonstrated their proposed method for separating (sorting) temporal modes by using a novel form of optical frequency conversion. Unlike polarization, which is fundamentally a two-state system, the temporal-mode basis offers the possibility for multi-level quantum logic (qudits). For TMs to rise to their potential as a tool for quantum information science, it needs to be demonstrated that all of the quantum resources and operations needed for QIS with temporal modes are available. Specifically, the researchers will work to demonstrate: 1) a source of TM-entangled photons, 2) quantum state tomography in the TM basis, 3) quantum process tomography of the QPG device itself, and 4) coherent and efficient manipulation of light in field-orthogonal TMs to implement single-photon quantum logic gates. Controlling the states of quantum systems is of broad interest in science and information technology, metrology, quantum chemistry, and nano-mechanics. Optical technology and quantum-optics-based information science offer excellent opportunities to integrate research with science education. The PI cofounded in 2010 the Science Literacy Program (SLP) at the University of Oregon, and served as Co-Director, and is currently on the Advisory Board. The SLP provides mentored instructional opportunities to many graduate students and undergraduate science majors serving as co-instructors in science literacy courses, which have impacted thousands of students at the university. During this project the PI will teach and mentor instructors for an SLP course that presents quantum information science to non-science majors, using inquiry-based-learning techniques to engage students. The PI has published a popular-level book for the course, Quantum Physics: What Everyone Needs to Know (Oxford, 2017), and will continue promoting education using material from this book as part of this project. A PhD student working in quantum information science research served as co-instructor to plan the course learning goals, prepare and present several class lectures, write homework and exam questions, and facilitate group problem-solving activities during class sessions.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.