Photon Queue Raises Oversubscribed Seed Round to Scale Quantum Memory Systems

Company is delivering free-space quantum memory technology to Sandia National Laboratories and the University of Maryland to address a critical bottleneck to scaling quantum networks.

CHAMPAIGN, Ill.--(BUSINESS WIRE)--Photon Queue, a quantum technology company building high-efficiency quantum memories for next-generation quantum computing systems, today announced the close of its oversubscribed seed funding round of $4 million, led by Playground Global. The seed round builds on Photon Queue’s early customer traction, including contracts with Sandia National Laboratories and the University of Maryland that validate demand from leading institutions at the forefront of quantum computing and photonic systems research.

The funding will accelerate Photon Queue’s product development, manufacturing capabilities and customer deployments as the company scales to meet demand from quantum computing companies, national laboratories and research institutions.

Quantum computing depends on photons arriving at exactly the right place and time. As systems scale, quantum platforms will need to network many smaller processors together, creating a universal bottleneck: synchronizing single photons across complex quantum systems. Quantum memories solve that problem by storing photons until they are needed.

Photon Queue’s devices store photons directly in free-space optical loops using proprietary high-reflectivity mirror systems and optical switches. Unlike other approaches that require cryogenics, vacuum systems or complex transduction processes, Photon Queue’s devices operate at room temperature using standard power, while delivering ultra-high efficiency and world-leading bandwidth.

“Useful quantum computing will require photons to move through networks with extraordinary precision, efficiency and timing. That is the problem Photon Queue was founded to solve,” said Nathan Arnold, co-founder and CEO of Photon Queue. “In less than two years, we have taken technology from the lab to deployed commercial hardware with leading national lab and university customers. Our work with Sandia and the University of Maryland is a major validation point that quantum memory is becoming essential infrastructure for the next era of computing.”

Photon Queue’s devices are designed to be compatible with virtually any wavelength, making them broadly applicable across photonic, trapped ion, neutral atom and other quantum computing architectures. The company has deployed its first commercial quantum memory device at Sandia National Laboratories and the University of Maryland.

“Quantum computing is hitting a scale problem that better qubits alone cannot solve. The industry needs new infrastructure to move, store and synchronize photons with far greater efficiency,” said Marissa Ramirez de Chanlatte, Investor at Playground Global. “Photon Queue has built an elegant solution, turning breakthrough quantum optics into commercial hardware, with early customer traction. We believe they are a foundational company that will define the quantum memory category.”

“Quantum memories are a critical enabling technology for distributed quantum systems, and performance, efficiency and ease of integration are essential,” said Saikat Guha, Clark Distinguished Chair Professor of Electrical and Computer Engineering at the University of Maryland, College Park and director of the NSF Center for Quantum Networks. “Photon Queue’s room-temperature, free-space approach is compelling because it stores photons directly without the complexity of cryogenics, vacuum systems or transduction. We look forward to working with the Photon Queue team as they continue developing practical quantum memory hardware for our research in quantum networking, sensing, and communication”

Founded in 2024 as a spinout from the University of Illinois Urbana-Champaign, Photon Queue is led by co-founders Nathan Arnold, CEO and Kelsey Ortiz, CTO. The founding team brings deep expertise in quantum optics, photonic systems and hardware commercialization.

Photon Queue is a graduate of the Duality Quantum Accelerator, a corporate partner of the Chicago Quantum Exchange and the winner of the Q2B Startup Pitch Competition. CEO Nathan Arnold is also a fellow at Chain Reaction Innovations at Argonne National Laboratory, a U.S. Department of Energy entrepreneurship program.

Photon Queue also recently announced $500,000 in funding from the New Mexico Economic Development Department and Roadrunner Venture Studios to support its expansion in New Mexico and deepen its work with the region’s national laboratory and quantum technology ecosystem.

About Photon Queue

Photon Queue is the world’s leading developer of free-space quantum memory devices. Founded in 2024 as a spinout from the University of Illinois Urbana-Champaign, the company builds high-performance quantum memories that store photons using linear optics at room temperature — delivering ultra-high efficiency and world-leading bandwidth with no cryogenics, vacuum systems or complex transduction required. Photon Queue’s technology serves quantum computing, communications and metrology applications. The company is headquartered in Champaign, Illinois. Learn more at photonqueue.com.

About Playground Global

Playground Global is a venture capital firm backing the most technically ambitious founders of working at the edge of engineering and science. With $1.7 billion under management, Playground invests in companies defining the future of next-generation compute, automation, energy, and engineered biology. Founded in 2015 and based in Palo Alto, California. Playground’s portfolio includes PsiQuantum, MosaicML (acquired by Databricks), d-Matrix, Agility Robotics, Ultima Genomics, and Strand Therapeutics. Learn more at www.playground.vc.

About Playground Genesis Fund

The Playground Genesis Fund is a $50 million investment fund operated by Playground Global with the support of the State Investment Council of New Mexico. The fund is designed to accelerate the commercialization of frontier technologies at the intersection of quantum science and advanced computing, while strengthening New Mexico’s role as a national hub for deep technology innovation. Playground Genesis invests in quantum and enabling technologies, including advanced computing hardware, quantum algorithms and software, infrastructure critical to next-generation computing systems, quantum sensing, advanced manufacturing and supply chain companies. To qualify for investment, companies must have material business relationships in New Mexico, including collaborations with Los Alamos National Laboratory and Sandia National Laboratories. The Playground Genesis Fund aims to translate breakthrough research into durable, high-impact companies that advance U.S. technological leadership and drive regional economic growth.