Quantum photonic processors generate, process, and measure quantum states of light on-chip to provide exponential advantages in computation, simulation, and communication. But such processors are also very sensitive to noise and loss. To realize practical quantum photonic processors that can solve useful problems requires quantum error correction which, like classical error correction, incorporates redundancy in order to protect the information from faults in the system. But the realization of these error correcting codes with photons is extremely challenging and requires very efficient photon sources, mode transformations, and single photon nonlinearities. Recent progress in integrated photonics and quantum optics has provided these core individual components, but integrating them into complex fault-tolerant systems remains extremely challenging. This program aims to combine large-scale silicon photonics, quantum emitters, and strongly nonlinear materials to build next generation quantum photonics processors that can protect quantum information using error correction. To address this challenging goal, the principal investigators will combine state-of-the-art quantum dot sources and nonlinearities with foundry based silicon photonics, a scalable and CMOS-compatible photonic platform. New fabrication approaches will be developed to combine these disparate components into a single device structure that can manipulate and interact photons with each other at an unprecedented scale. These devices will operate at the technologically important telecommunications band, and could potentially interfaced with existing infrastructure to develop continental-scale unconditionally secure communication networks. They could also implement next generation quantum algorithms advancing drug design, materials science and big data -- all at a scale where classical machines can no longer keep pace. This program will also contain a significant outreach effort aimed at developing the next generation of quantum engineers by mentoring, new curriculum development, and the development of a youtube channel for quantum engineering.
A key goal of this program is a unification of the core individual hardware components into a single system that can efficiently process quantum states of light on a semiconductor chip. These core components include single photon sources, high-fidelity mode transformations, and strong single-photon nonlinearities. By bringing together a combination of complementary expertise in large-scale silicon photonics design, quantum emitter spectroscopy, and nano-fabrication of CMOS control, this proposal will develop systems level solutions to build next generation quantum photonics processors that can perform photonic quantum error correction, the key ingredient for scalable quantum information processing. To generate single photons, the team will utilize high-efficiency single photon sources based on InAs quantum dots. Large-scale Si photonic circuits will apply complex linear mode transformations on generated photons. Finally, cavity-coupled quantum dots in the strong coupling regime will implement single photon nonlinearities to generate two-qubit interactions. Hybrid fabrication techniques will be leveraged to combine different material platforms into a single circuit that can implement photonic error correction for loss, the dominant fault mechanism for photonic qubits. Such loss error correction codes are essential for any scalable quantum information processing application including photonic quantum computers and one-way quantum repeaters that can attain long distance and high speeds simultaneously.
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.
