Next-Gen Quantum Computing: The Fusion of Atoms and Photonic Innovation

By University of Chicago November 29, 2024

Collected at: https://scitechdaily.com/next-gen-quantum-computing-the-fusion-of-atoms-and-photonic-innovation/

Researchers at the University of Chicago have developed a new method for enhancing quantum information systems by integrating trapped atom arrays with photonic devices.

This innovation allows for scalable quantum computing and networking by overcoming previous technological incompatibilities. The design features a semi-open chip that minimizes interference and enhances atom connectivity, promising significant advances in computational speed and interconnectivity for larger quantum systems.

Merging Technologies for Enhanced Quantum Computing

Quantum information systems promise faster, more powerful computing capabilities than traditional computers, offering potential solutions to some of the world’s most complex challenges. However, achieving this potential requires building larger, more interconnected quantum computers—something scientists have yet to fully realize. Scaling these systems to larger sizes and linking multiple quantum systems together remains a significant challenge.

Researchers at the University of Chicago’s Pritzker School of Molecular Engineering (PME) have made a breakthrough by combining two advanced technologies: trapped atom arrays and photonic devices. This innovative approach enables the creation of scalable quantum systems by using photonics to interconnect individual atom arrays, paving the way for advancements in quantum computing, simulation, and networking.

“We have merged two technologies which, in the past, have really not had much to do with each other,” said Hannes Bernien, Assistant Professor of Molecular Engineering and senior author of the new work, published in Nature Communications. “It is not only fundamentally interesting to see how we can scale quantum systems in this way, but it also has a lot of practical applications.”

Challenges of Integrating Photonics With Atom Arrays

Arrays of neutral atoms trapped in optical tweezers—highly focused laser beams that can hold the atoms in place—are an increasingly popular way of building quantum processors. These grids of neutral atoms, when excited in a specific sequence, enable complex quantum computation that can be scaled up to thousands of qubits. However, their quantum states are fragile and can be easily disrupted—including by photonic devices that aim to collect their data in the form of photons.

“Connecting atom arrays to photonic devices had been quite challenging because of the fundamental differences in the technologies. Atom array technology relies on lasers for their generation and computation.” said Shankar Menon, a PME graduate student and co-first author of the new work. “As soon as you expose the system to a semiconductor or a photonic chip, the lasers get scattered, causing problems with the trapping of atoms, their detection, and the computation.”

New Semi-Open Chip Design for Quantum Computing

In the new work, Bernien’s group developed a new semi-open chip geometry allowing atom arrays to interface with photonic chips, overcoming these challenges. With the new platform, quantum computations can be carried out in a computation region, and then a small portion of those atoms containing desired data are moved to a new interconnect region for the photonic chip integration.

“We have two separate regions that the atoms can move between, one away from the photonic chip for computation and another near the photonic chip for interconnecting multiple atom arrays,” explained co-first author Noah Glachman, a PME graduate student. “The way this chip is designed, it has minimal interaction with the computational region of the atom array.”

Enhanced Connectivity and Speed With Nanophotonic Cavities

In the interconnect region, the qubit interacts with a microscopic photonic device, which can extract a photon. Then, the photon can be transmitted to other systems through optical fibers. Ultimately, that means that many atom arrays could be interconnected to form a larger quantum computing platform than is possible with a single array.

An additional strength of the new system—which could lead to especially speedy computation abilities—is that many nanophotonic cavities can be simultaneously connected to one single atom array.

“We can have hundreds of these cavities at once, and they can all be transmitting quantum information at the same time,” said Menon. “This leads to a massive increase in the speed with which information can be shared between interconnected modules.”

Future Directions and Research

While the team showed the feasibility of trapping an atom and moving it between regions, they are planning future studies that look at other steps in the process, including collection of the photons from the nanophotonic cavities, and the generation of entanglement over long distances.

Reference: “An integrated atom array-nanophotonic chip platform with background-free imaging” by Shankar G. Menon, Noah Glachman, Matteo Pompili, Alan Dibos and Hannes Bernien, 22 July 2024, Nature Communications.
DOI: 10.1038/s41467-024-50355-4