Ann Arbor Times

Researchers and students at the University of Michigan can now conduct remote quantum experiments on campus, following the creation of a new quantum testbed that connects two laboratories via optical fibers. The initiative is designed to broaden access to quantum technology tools and establish an educational resource using experimental data.

Quantum research often relies on theoretical work due to limited facilities for practical testing. Phenomena such as entanglement, where two particles are linked so that measuring one affects the other instantly, are typically tested only at select locations with restricted in-person access. Many researchers lack resources to travel or collaborate across multiple labs, limiting opportunities to experiment with entangled light over long distances.

The new optical fiber link connects the labs of Zheshen Zhang and Parag Deotare, both associate professors of electrical and computer engineering. Their facilities—located in the Electrical Engineering and Computer Science Building on North Campus and Randall Laboratory on Central Campus—are about three miles apart. This connection allows encrypted or entangled information to be transferred between the sites using light.

While transferring information through glass fibers is common in internet infrastructure, sending quantum information (qubits) over these fibers has potential implications for communication, computing, and scientific research due to its speed and privacy features.

“You can think about this link as an extension of the current internet, with telecommunication fibers transmitting optical signals, but now we have the new capability to distribute quantum states of light in addition to classical states of light,” Zhang said.

The team has already demonstrated successful transport of entangled light across the link. They have also created interactive demonstrations available at qreal.cloud that let users learn quantum theory concepts and see real experimental data collected from the testbed.

Access to hardware needed for generating quantum states or conducting other experiments has traditionally been limited to well-funded institutions. This restricts broader participation from universities or industry partners without such resources. Zhang and Deotare aim to address this barrier by enabling remote access.

“If we can create a portal that allows external users to remotely access the testbed resources, that greatly facilitates technology advancement and technology transfer,” Zhang said.

The project’s scope includes expanding connections within the University of Michigan as well as linking with other local universities and industries. The goal is a larger-scale network supporting diverse quantum experimentation.

“Part of this project is also education and workforce development,” Deotare said. “The distributed network that we’re creating would serve as excellent infrastructure for industry folks to visit and spend a couple of weeks trying to understand quantum experiments at a distributed network level and getting experience with an actual system.”

Existing fiber infrastructure in Ann Arbor supports these efforts. The team is working with Merit Network—a service provider managing local telecommunication links—to extend their network further into community colleges and industries.

Currently, equipment between the two labs enables both creation and detection of entanglement. Plans include adding more labs using different physical platforms such as neutral atoms, 2D materials, trapped ions, and superconducting qubits—all present at Michigan.

“Our testbed would serve as the backbone of interconnecting quantum systems, and, in turn, advance the development of different quantum systems,” Zhang said. “Our vision is that the testbed becomes a local engine for innovation and workforce development.”

Ph.D. students Alexander McFarland, Visuttha Manthamkarn, and Kailu Zhou contributed significantly by setting up connections and remote testing capabilities. Funding came from the U-M Office of the Vice President for Research for research activities; educational components received support from the National Science Foundation.