EAGER: Quantum Information in Complex Systems

在化学系化学结构、动力学和机制A （CSDM-A）项目的支持下，普林斯顿大学的Gregory Scholes教授正在推进在分子系统中创建和量化量子纠缠的方法。根据我们自己的经验，我们知道对两个独立粒子的测量，就像抛两枚硬币一样，是不相关的。也就是说，第二枚硬币正面（或反面）落地与第一枚硬币落地没有关系。然而，当粒子表现出量子力学行为时，情况就不一定是这样了。在量子力学中，两个粒子可以纠缠在一起，从而产生相关的观测结果。就好像每次第一枚硬币正面朝上，第二枚硬币也会正面朝上。如果第一枚硬币是反面，那么第二枚硬币也是反面，即使两枚硬币相隔很远。斯科尔斯教授和他的学生们正在研究量化和演示分子系统中纠缠的方法，这仍然是一个重大的实验挑战。他们的发现可能会对量子信息科学与工程（QISE）产生广泛的影响，并为创建基于量子的计算、传感和通信技术带来新的方法。该项目旨在开发一种基于量子费雪信息（QFI）的通用形式，用于量化量子相关性（例如，纠缠），并将这种形式应用于分子发色团和发色团组合的实验观察。作为该方法的初步演示，Scholes教授和他的学生将尝试使用他们的方法，通过测量模型分子二聚体和紫色细菌的光收集复合体（LH2）的瞬态光谱中的QFI程度，来量化量子相关性。此外，以经典相位同步的概念为灵感，该团队还试图证明量子效应可能在大尺度上被发现为稳定的相位。从这项工作中获得的见解可以指导其他人寻求量化复杂分子系统和组件中的量子相关性，从而实现新的研究途径。该项目还将通过为参与这项工作的学生和博士后学者提供QISE研究的高级培训，为国家量子劳动力的发展做出贡献。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

With support from Chemical Structure, Dynamics, and Mechanisms A (CSDM-A) program in the Division of Chemistry, Professor Gregory Scholes of Princeton University is advancing methods to create and quantify quantum entanglement in molecular systems. From our own experience, we know that measurements made on two independent particles, like the flipping of two coins, are uncorrelated. That is, whether the second coin lands heads (or tails) has no relationship to how the first coin landed. However, this is not necessarily the case when the particles behave quantum mechanically. In quantum mechanics, two particles can be entangled resulting in correlated observations. It would be as if every time the first coin landed heads, the second coin would also land heads. And if the first coin were tails, the second would be too, even if the two coins were separated by a great distance. Working with his students, Professor Scholes is developing ways to quantify and demonstrate entanglement in molecular systems, which remains a significant experimental challenge. Their discoveries could have broad implications for quantum information science and engineering (QISE), and lead to new ways to create quantum-based technologies for computing, sensing, and communications. The project seeks to develop a general formalism based on quantum Fisher information (QFI) for quantifying quantum correlations (e.g., entanglement) and apply this formalism to experimental observations made on molecular chromophores and chromophore assemblies. As an initial demonstration of the method, Professor Scholes and his students will attempt to use their approach to quantify quantum correlations by measuring the degree of QFI in the transient spectra of model molecular dimers and of the light harvesting complex (LH2) from purple bacteria. In addition, with the concept of classical phase synchronization used as inspiration, the team is also seeking to demonstrate that quantum effects might be discovered as a stable phase on large scales. The insights gained from this work could guide others seeking to quantify quantum correlations in complex molecular systems and assemblies, enabling new avenues of research. This project also will contribute to the development of a national quantum-enabled workforce by providing advanced training in QISE research for the students and postdoctoral scholars participating in the work.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.