CAREER: Entanglement Engineering in Dissipation-Driven Quantum Systems

非技术摘要量子信息处理(QIP)已迅速成为一个引人注目的研究方向，这是由于量子计算机能够执行对任何当前或可想象的未来经典(非量子)超级计算机来说太大的计算的前景。QIP的致命弱点是耗散，这种摩擦既会产生热量，又会破坏QIP所需的量子比特(量子比特)之间的长期量子关联，到目前为止，这限制了量子信息系统的规模和复杂性。量子比特之间的这种关联被称为纠缠，这项研究的目标是产生任何所需的量子比特纠缠态，这成为量子计算的起点。解决这个普遍问题的一个强有力的方法是量子水库工程：想法是打开耗散的表，并将其用作指导量子系统的资源，使得耗散驱动的动力学自然地将系统松弛到感兴趣的状态。这个职业项目支持开发一种新的水库工程框架的基础研究，并利用它在嘈杂的量子系统中产生纠缠。从实践的角度来看，这将有助于确定将油藏工程建立为可扩展和强大的纠缠产生的标准范例的关键里程碑，该范例在量子信息科学的所有领域都有应用，包括量子计算、传感和通信。此外，拟议的研究将通过开发理论工具来严格探索标准耗散模型在随时间变化且相互关联的噪声存在下的有效性，从而使与噪声环境耦合的量子系统物理学取得根本性进展。本项目的教育和培训方面将采取多管齐下的方法，使研究生和本科生接触到量子信息和量子光学中的各种分析和计算技术。在与固态量子比特实验实现的密切联系的帮助下，目的将是为受训人员提供QIP多语种领域的整体看法，并满足国家创造一支“量子智能”劳动力的战略需要。培训方面将与广泛的教育和推广目标相结合，通过新的和持续的课程开发倡议、公共演讲和促进开放获取场所来交流研究成果。技术摘要量子水库工程是一种有吸引力的方法，用于自动纠正错误和实现稳定的量子相干。基本思想是定制目标系统的耗散环境，以便这种工程设计的耗散将系统松弛到并维持在所需的目标状态。虽然现有的耗散状态准备方案是通用的，但它们完全依赖于与时间无关的耗散动力学，这可能会使协议容易受到不必要的虚假耗散的影响。PI的广泛愿景是，该项目将使一类变革性的耗散状态准备协议具有显著提高的速度、保真度和对错误的稳健性。为此，研究将主要集中在两个方向：(I)研究依赖于时间的耗散驱动的动力学；(Ii)研究由相关耗散驱动的动力学。这些理论研究将涉及开发一个全面的分析和数值框架，其中一些是对开放量子系统描述的有效性的初步探索，特别是在非平凡耗散是有用资源的背景下。例如，该项目的成果将解决与绝热性和非马尔可夫性对油藏工程的影响有关的基本问题，并为在存在相关噪声的情况下进行量子误差校正和误差缓解提供有用的指示。这不仅对这里设想的纠缠稳定协议，而且对任何涉及量子系统动态控制的平台都具有变革的潜力。PI与实验小组保持着积极的合作，这些小组将在约瑟夫森结超导平台上测试这些想法。因此，这项研究将在短期内补充和推进低维开放系统量子控制方面快速增长的实验能力。此外，它将有助于加强量子信息/量子光学、最优控制和强相互作用场论等不同领域之间的跨学科联系，所有这些领域都专注于远离平衡的量子动力学。该奖项反映了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。

Non-technical AbstractQuantum information processing (QIP) has rapidly emerged as a compelling research direction, driven by the prospect of quantum computers capable of performing calculations that are too large for any current or conceivable future classical (non-quantum) supercomputer. The Achilles heel of QIP has been dissipation, the friction that both generates heat and destroys the long-lived quantum correlations among quantum bits ("qubits") necessary for QIP, so far limiting quantum information systems in both size and complexity. Such correlations among qubits are called "entanglement," and a goal of this research is to produce any desired entangled state of qubits, which becomes the starting point for a quantum computation.A powerful approach to address this general problem is quantum reservoir engineering: the idea is to turn the tables on dissipation and use it as a resource for steering a quantum system, such that the dissipation-driven dynamics naturally relax the system to the state of interest. This CAREER project supports basic research into developing a novel reservoir engineering framework and leverages it for entanglement generation in noisy quantum systems. From a practical standpoint, this will help identify critical milestones for establishing reservoir engineering as a standard paradigm for scalable and robust entanglement generation, which has applications in all areas of quantum information science, including quantum computing, sensing and communication. In addition, the proposed research will enable fundamental advances in the physics of quantum systems coupled to a noisy environment by developing theoretical tools to rigorously explore the validity of standard dissipative models in the presence of noise that varies, and is correlated, in time.The education and training aspect in this project will assume a multi-pronged approach that will expose graduate and undergraduate students to a wide variety of analytical and computational techniques in quantum information and quantum optics. Aided and informed by close connections with experimental realizations of solid-state qubits, the aim will be to provide the trainees a holistic view of the polyglot field of QIP and address the strategic national need to create a "quantum-smart" workforce. The training aspect will be integrated with broad educational and outreach goals via new and continuing curriculum and course development initiatives, public talks, and promoting open access venues for communicating research results.Technical AbstractQuantum reservoir engineering is an attractive approach for correcting errors and realizing stable quantum coherences autonomously. The basic idea is to tailor the dissipative environment of the target systems so that this engineered dissipation relaxes the system to and sustains it in a desired target state. While versatile, existing schemes for dissipative state preparation rely exclusively on time-independent dissipative dynamics, which can leave the protocols susceptible to unwanted spurious dissipation. The PI's broad vision is that this project will enable a transformative new class of dissipative state preparation protocols with dramatically improved speed, fidelity and robustness to errors. To this end, the research will broadly focus on two directions: (i) study of dynamics driven by time-dependent dissipation, and (ii) study of dynamics driven by correlated dissipation. These theoretical studies will involve developing a comprehensive analytical and numerical framework with some of the first explorations of the validity of open quantum systems descriptions, especially in a context where non-trivial dissipation is a useful resource. For instance, the outcomes of this project will address fundamental questions pertaining to implications of adiabaticity and non-Markovianity for reservoir engineering and provide useful pointers for quantum error correction and error mitigation in the presence of correlated noise. This has transformative potential not only for the entanglement stabilization protocols envisioned here but also for any platform involving dynamic control of quantum systems. The PI maintains an active collaboration with experimental groups who will test the ideas on Josephson-junction-based superconducting platforms. Thus this research will complement and advance the rapidly growing experimental capabilities in quantum control of low-dimensional open systems in the near-term. Further, it will help strengthen interdisciplinary connections between disparate fields of quantum information/quantum optics, optimal control and strongly-interacting field theories, all of which focus on far-from-equilibrium quantum dynamics.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.