EAGER: QIA: A quantum algorithm for detecting quantum information leakage in qubit systems

在量子计算机中，信息以量子比特的形式编码，即量子位。理想情况下，量子比特是一个两级量子系统，代表逻辑状态“0”和“1”。在超导通量量子比特和俘获离子这两种领先的量子计算平台中，量子比特中编码的量子信息容易发生泄漏。因此，信息泄露是影响我们在近期量子计算设备上成功进行计算的能力的主要错误来源之一。本项目开发并实验测试了一种新的量子算法，通过利用量子系统中的强相关性纠缠来检测量子比特系统中的特定泄漏误差。由于这些强相关性，该算法可以准确检测泄漏误差，比最先进的泄漏检测协议所需的实验运行次数少得多。有效和精确地检测特定的信息泄漏错误对于当前最先进的量子计算平台的发展至关重要，反过来又提高了我们在整个科学和工程中执行更精确的量子计算任务的能力。本项目的科学目标是利用强相关（纠缠）二部量子系统开发检测潜在泄漏通道的量子算法。系统之间的相关性专门用于探测和检测特定的泄漏误差通道。该算法适用于检测任何关注的泄漏通道，且具有灵活性；它是确定性的，允许人们以概率1来检测特定的泄漏通道。参与该项目的pi和学生正在当前可用的量子计算设备上测试和基准测试算法。因此，泄漏检测算法的成功开发和实现增强了我们抑制它们的能力，进而提高了当前可用量子计算平台的性能。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。

In quantum computers, information is encoded in quantum bits, that is, qubits. Ideally a qubit is a two-level quantum system, representing the logical states "0" and "1". In the two leading quantum computing platforms, superconducting flux qubit and trapped ions, quantum information encoded in the qubit is prone to leakage. As a consequence, information leakage is one of the main sources of errors that affect our ability to perform successful computing on near-term quantum computing devices. This project develops and experimentally tests a novel quantum algorithm for detecting specific leakage errors in qubit systems by harnessing entanglement, which are the strong correlations in quantum systems. Thanks to these strong correlations, the algorithm allows an accurate detection of the leakage errors with substantially fewer experimental runs than required by state-of-the-art leakage detection protocols. Efficiently and precisely detecting specific information leakage errors is crucial for the current advancement of state-of-the-art quantum computing platforms, and in turn increases our ability to perform more precise quantum computing tasks with relevance throughout science and engineering. The scientific goals of this project is to develop quantum algorithm for detecting potential leakage channels by using strongly-correlated (entangled) bipartite quantum systems. The correlations between the systems are specifically designed to probe and detect particular leakage error channels. The algorithm is suitable and has the flexibility to detect any leakage channel of concern; it is deterministic and allows one to detect the specific leakage channels with probability one. The PIs and the student involved in this project are testing and benchmarking the algorithm on currently available quantum computing devices. The successful development and implementation of a leakage detection algorithm thus enhances our ability to suppress them, and in turn enhances the performance of currently available quantum computing platforms.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.