Quantum Breakthroughs: NIST & SQMS Lead the Way

While quantum computing might seem like technology for the distant future, the breakthroughs from the collaboration between Fermilab’s Superconducting Quantum Materials and Systems (SQMS) Center, the National Institute of Standards and Technology (NIST), and several other government, university, and industrial partners, could reshape industries and daily life in the near future. NIST is dedicated to pushing the frontiers of quantum computing and making that technology viable, scalable, and energy efficient. 

Scientists from NIST’s Communications Technology Laboratory (CTL) and the Physical Measurement Laboratory (PML) are leading the SQMS Center’s Nanofabrication Taskforce, a joint effort aimed at enhancing the performance of superconducting quantum bits (qubits) — the building blocks of quantum computers. Taskforce members from the CTL Superconductive Electronics Group, and the PML Quantum Sensors Group and Advanced Microwave Photonic Group contribute expertise in metrology, nanofabrication, and materials science to the SQMS Nanofabrication Taskforce efforts. A key player in this effort is Peter Hopkins, who leads a team from the NIST CTL Superconductive Electronics Group. Under his guidance, the team has pioneered breakthroughs in qubit fabrication techniques, such as encapsulating the surface of qubits made from the chemical element niobium, a superconducting metal, to reduce material losses and extend qubit coherence times significantly.

Why is the SQMS Nanofabrication Taskforce Important?

The taskforce is tackling one of the biggest challenges in quantum computing: improving qubit coherence. Longer coherence times mean qubits can maintain their quantum states longer, leading to more powerful and reliable quantum computers. This work is crucial for:

• Advancing Quantum Computing: Improving superconducting qubits brings us closer to solving complex problems that classical computers cannot handle.
• Boosting U.S. Technological Leadership: The U.S. is in a global race to lead in quantum technology, and SQMS plays a vital role in keeping our nation ahead.
• Fostering Collaboration: The taskforce unites national labs, academia, and industry to create standardized, scalable quantum fabrication processes.
• Economic and National Security Impacts: From revolutionizing cybersecurity (quantum-safe encryption) to advancing materials science and AI, quantum computing has far-reaching implications.

Quantum computing may seem abstract, but its real-world implications are practical and widespread. The quantum research being done will lead to better healthcare due to quantum computers accelerating drug discovery and other medical research. Stronger cyber security measures and encryption methods protecting sensitive data will become available as quantum computers evolve. There is also an opportunity for economic growth as the U.S. invests in quantum technology that will lead to new industries forming, high-tech jobs becoming available, and economic expansion across the many sectors affected by quantum technology.

Key Technical Breakthroughs

Recent innovations by the SQMS Nanofabrication Taskforce have led to a systematic improvement in qubit coherence, with the best-performing qubits now reaching coherence times of up to 0.6 milliseconds, a significant leap for superconducting quantum technology. This achievement is driven by optimized qubit designs and enhanced readout resonators, which improve qubit stability and coherence. Additionally, researchers have tackled qubit loss mechanisms by encapsulating niobium surfaces with gold or tantalum to prevent the formation of lossy niobium oxide, a major source of decoherence. Efforts are also underway to explore alternative materials for Josephson junctions, addressing losses caused by aluminum oxide tunnel barriers, while recognizing that other material interfaces and sapphire substrates currently limit coherence times to approximately 1 millisecond. To push the boundaries of performance even further, the taskforce is investigating new superconducting materials, while also refining Josephson tunnel junction fabrication techniques. In addition to the advancements in materials, nanofabrication process optimizations, such as reducing processing steps and developing sidewall capping techniques, are enhancing the reliability and scalability of quantum hardware, paving the way for next-generation quantum computing.

The Future of Quantum Computing with SQMS

The breakthroughs from the SQMS Nanofabrication Taskforce bring quantum research closer to the ultimate goal: building scalable, fault-tolerant quantum computers. By tackling the fundamental challenges of qubit fabrication and coherence, NIST scientists from CTL and PML help to ensure the U.S. remains a leader in this transformative field.