Collaborative Research: Toward universal quantum computing with heterogeneously integrated quantum optical frequency combs

合作研究：利用异构集成量子光学频率梳实现通用量子计算

• 批准号: 2219760
• 负责人: Mario Dagenais
• 金额: $ 36万
• 依托单位: University of Maryland, College Park
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2219760&HistoricalAwards=false
• 关键词: Collaborative; Research; Toward; universal; quantum

Quantum computing is a disruptive technology capable of solving classically intractable problems, such as factoring integers and breaking encryption codes, and performing quantum simulations of major societal impact such as nitrogen fixation for fertilizer production, carbon dioxide fixation for carbon sequestration, and unlocking room-temperature superconductivity. The route toward full scale quantum computing faces daunting challenges. One approach away from the dominant quantum gate approach is measurement-based quantum computing, and, in particular, one-way quantum computing using cluster states. This approach circumvents the requirement of low decoherence and memories for scalability. Our approach is purely based on using photons, operates at room-temperature, and uses a wavelength compatible to present optical communication networks. Large two-dimensional cluster states will be produced using quantum optical frequency combs. These cluster states are deterministically and unconditionally generated and scale exponentially. The cluster states are based on continuous-variable quantum optical systems and are encoded over quantum fields. The key objective of this proposal is to demonstrate the generation of continuous variable cluster states on chip and to demonstrate the preparation of resource states called Gottesman-Kitaev-Preskill (GKP) grid states, which are key to error correction and to universal quantum computing. To realize the chip-scale quantum state generator, hetero-integration of different platform technology on a silicon board will be used. In particular, a high quality factor (Q) nanocavity using gratings will be realized on the SiN/SiO2 platform and will produce an optical frequency comb. A narrow linewidth semiconductor laser based on a III-V gain chip coupled to a high Q cavity will be mounted on the Si platform. Finally, a thin-film LiNbO3 modulator for high speed modulation will be heterogeneously integrated on the Si platform. A broad impact plan will be set-up to educate high school students in quantum physics, train under-represented groups in quantum engineering, and educate graduate students for success in engineering research.A realistic path to quantum computation requires the implementation of standalone chipscale systems to create and manipulate quantum states of light. These systems should ideally operate at room temperature and at wavelengths compatible with those of classical optical communication systems. In this project, a novel integrated platform to realize some basic quantum protocols with high efficiency and fidelity will be demonstrated. The proposal aims at the first realization of cluster states, cat states, and Gottesman-Kitaev-Preskill (GKP) states on a photonic chip, with the overarching goal of realizing all the required building blocks for a fault-tolerant photonic quantum computer. Measurement based quantum computation primitives, namely, feedforward on cluster states informed by field-homodyne and photon-number-resolving (PNR) detection will be realized. The experimental platform is based on one optical parametric oscillator and one electro-optic phase modulator integrated on Si. The core of the envisioned quantum system is an integrated millimeter-size grating Fabry-Perot resonator, featuring a free-spectral range of a few tens of GHz and a Q-factor better than a million at 1550 nm. The Si3N4 microresonator is pumped by a co-integrated narrow-linewidth single mode laser, and owing to the built-in Kerr nonlinearity of the medium, outputs quantum-correlated photons distributed in the spectral modes of an optical frequency comb. High-efficiency optical coupling from chip to optical fibers will be used to interface with photodetection. The first experimental objective is to demonstrate large-scale cluster state generation on chip. The second experimental objective is to demonstrate non-Gaussian (e.g. cat and GKP) state generation on chip, using PNR detection measurements. The full spectrum of possibilities of this quantum photonic chip will also be studied in microresonator optical parametric oscillators operated above threshold.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.

量子计算是一种颠覆性技术，能够解决经典的棘手问题，例如整数因式​​分解和破解加密代码，并对重大社会影响进行量子模拟，例如化肥生产的固氮、碳封存的二氧化碳固定以及解锁室温超导。全面量子计算的道路面临着艰巨的挑战。一种不同于主流量子门方法的方法是基于测量的量子计算，特别是使用簇状态的单向量子计算。这种方法规避了低退相干和可扩展性存储器的要求。我们的方法纯粹基于使用光子，在室温下运行，并使用与现有光通信网络兼容的波长。大型二维簇态将使用量子光学频率梳产生。这些集群状态是确定性且无条件生成的，并且呈指数级扩展。簇态基于连续可变量子光学系统，并在量子场上进行编码。该提案的主要目标是演示芯片上连续可变簇状态的生成，并演示称为 Gottesman-Kitaev-Preskill (GKP) 网格状态的资源状态的准备，这是纠错和通用量子计算的关键。为了实现芯片级量子态发生器，将使用不同平台技术在硅板上的异质集成。特别是，将在 SiN/SiO2 平台上实现使用光栅的高品质因数 (Q) 纳米腔，并将产生光学频率梳。基于与高 Q 腔耦合的 III-V 族增益芯片的窄线宽半导体激光器将安装在 Si 平台上。最后，用于高速调制的薄膜LiNbO3调制器将异构集成在Si平台上。将制定一项广泛的影响计划，以教育高中生量子物理学，培训量子工程方面代表性不足的群体，并教育研究生在工程研究中取得成功。通往量子计算的现实道路需要实施独立的芯片级系统创建和操纵光的量子态。 理想情况下，这些系统应在室温和与经典光通信系统兼容的波长下运行。在该项目中，将展示一种新颖的集成平台，以高效、保真地实现一些基本量子协议。该提案旨在首次在光子芯片上实现簇态、猫态和 Gottesman-Kitaev-Preskill (GKP) 态，总体目标是实现容错光子量子计算机所需的所有构建模块。基于测量的量子计算原语，即通过场零差和光子数分辨（PNR）检测通知的簇状态的前馈将被实现。该实验平台基于硅上集成的一个光参量振荡器和一个电光相位调制器。设想的量子系统的核心是集成的毫米级光栅法布里-珀罗谐振器，其自由光谱范围为几十GHz，在1550 nm处的Q因数优于一百万。 Si3N4微谐振器由共集成窄线宽单模激光器泵浦，并且由于介质的内置克尔非线性，输出分布在光学频率梳的光谱模式中的量子相关光子。从芯片到光纤的高效光学耦合将用于与光电检测连接。第一个实验目标是演示芯片上大规模簇状态的生成。第二个实验目标是使用 PNR 检测测量来演示芯片上的非高斯（例如 cat 和 GKP）状态生成。这种量子光子芯片的全部可能性也将在高于阈值运行的微谐振器光学参量振荡器中进行研究。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。