China Achieves 35.6 Tesla All-Superconducting Magnet World Record | CAS Breakthrough

Fundamentals of Superconducting Magnets Explained

Superconducting magnets represent a cornerstone of modern scientific research, leveraging materials that exhibit zero electrical resistance when cooled to cryogenic temperatures, typically near absolute zero using liquid helium or advanced cryocoolers. A Tesla (T), the unit of magnetic field strength named after Nikola Tesla, quantifies flux density; for context, a standard fridge magnet registers about 0.005 T, while this CAS magnet achieves 35.6 T—an immense leap.

The process begins with winding coils from superconducting wires, such as those incorporating rare-earth barium copper oxide (REBCO) high-temperature superconductors, which operate above traditional niobium-titanium limits. When current flows through these coils without resistance, persistent currents generate extraordinarily strong, uniform fields. All-superconducting designs, unlike hybrid systems combining superconducting outserts with resistive inserts, rely entirely on superconductors for both background and insert fields, minimizing energy use and heat generation while maximizing efficiency.

Historically, superconducting magnets evolved from early niobium-zirconium demonstrations in the 1960s to today's high-field REBCO-based systems. This progression has enabled facilities worldwide to push boundaries in condensed matter physics, where extreme fields reveal material properties invisible at lower strengths.

The Synergetic Extreme Condition User Facility: A Hub of Innovation

Located in Huairou Science City, the Synergetic Extreme Condition User Facility (SECUF) integrates ultra-low temperatures, high magnetic fields, ultra-high pressures, and ultrafast optics into a synergistic platform. Nationally accepted in February 2025, it serves as an open-access resource for domestic and international scientists, fostering collaborative experiments under compounded extremes.

The 35.6 T magnet resides at its ultra-low temperature high magnetic field quantum oscillation station, boasting a 35 mm usable bore—ample for sample insertion in techniques like nuclear magnetic resonance (NMR) spectroscopy. This bore size balances field strength with experimental practicality, a key engineering feat.

For higher education, SECUF exemplifies how national labs interface with universities, offering graduate students hands-on access to world-class tools. Institutions like Tsinghua University and Peking University frequently collaborate here, training the next generation of researchers.

Engineering the 35.6 Tesla Marvel: Design and Challenges

Crafting this magnet demanded innovations in high-temperature superconducting (HTS) inserts, structural optimization, and manufacturing precision. The core employs REBCO tapes for the innermost coils, surrounded by low-temperature superconductors for the outsert, all cryogenically cooled to maintain superconductivity. Key challenges included quenching risks—sudden loss of superconductivity causing field collapse—and mechanical stresses from Lorentz forces, which can exceed 100,000 tons in high-field setups.

Researchers upgraded materials for higher critical currents, refined winding techniques for uniformity, and implemented advanced quench protection via health monitoring systems. The result: a field homogeneity enabling precise quantum oscillation studies, with stability exceeding 200 hours at peak.

• Central field: 35.6 T
• Bore diameter: 35 mm
• Stability: >200 hours
• Energy efficiency: Near-zero resistance losses
• Integration: Compatible with mK temperatures and GPa pressures

These specs position it as the world's strongest all-superconducting user magnet above 30 T, a milestone for accessible high-field science.

The Visionary Team Driving CAS's Success

Leading the charge were researchers Li Gang, Liu Jianhua, and Zhou Benzhe from CAS's Institute of Electrical Engineering, who handled design, fabrication, and integration. The Institute of Physics contributed critical expertise in real-time monitoring and precision metrology, with Luo Jianlin highlighting its experimental versatility: "It can stably maintain its maximum magnetic field for more than 200 hours... greatly meeting the needs of the research community."

This interdisciplinary collaboration reflects CAS's model, blending engineering prowess with physical insights. For aspiring academics, such projects offer pathways into elite research roles; explore opportunities at higher-ed research jobs or China academic positions.

Milestones in Superconducting Magnet Records

CAS's trajectory includes a 32.35 T all-superconducting magnet in 2019 and 30 T user magnet in 2023 from the same team. Globally, the timeline traces to MagLab's 35.4 T hybrid in 2011 and NHMFL's records, but all-superconducting user facilities lag until this breakthrough.

Meanwhile, Hefei's SHMFF holds resistive records at 42 T, but those consume megawatts versus this magnet's efficiency. China's ascent mirrors investments in 'Strategic High-Tech' under the 14th Five-Year Plan, elevating its labs to parity with NIST and CERN.

Transforming Materials Science and Quantum Research

In materials science, 35.6 T fields unravel quantum phases in correlated electron systems, like high-Tc cuprates and heavy fermions. Quantum oscillations (SdH, dHvA) map Fermi surfaces with unprecedented resolution, revealing topological insulators and Weyl semimetals crucial for quantum computing.

Paired with SECUF's pressures up to 100 GPa, it simulates planetary cores or unveils superconductivity in hydrides. Chinese universities, such as USTC Hefei, leverage similar facilities for PhD theses driving publications in Nature and Science.

Practical insights: Researchers can now test magnetocaloric effects for efficient cooling, advancing cryogenics. For career advice, check academic CV tips.

Revolutionizing Life Sciences and Medical Innovations

Beyond physics, the magnet enables high-resolution NMR for biomolecular structures, accelerating drug discovery. Magnetic-targeted therapy uses fields to guide nanoparticles to tumors, minimizing side effects—a frontier for CAS-linked medical schools.

Specific heat and magnetostriction measurements probe protein folding under stress, informing neurodegenerative disease models. With 12-24x MRI fields, it paves for ultra-high-field imaging scanners revolutionizing diagnostics.Read the full CAS announcement

Boosting Higher Education and Research Careers in China

This breakthrough invigorates China's higher education landscape, where CAS institutes mentor thousands of graduate students annually. Universities like Tsinghua integrate high-field data into curricula, preparing students for postdoc positions and faculty roles.

• Training: Hands-on SECUF access for theses
• Funding: National Natural Science Foundation grants surging
• Careers: Demand for experts in HTS, cryogenics
• Global Mobility: Joint programs with MIT, Oxford

Explore university jobs or professor opportunities in China's booming research sector.

Photo by Liam Read on Unsplash

Global Implications and Future Horizons

Internationally, this magnet democratizes extreme-field access, outpacing facilities like Grenoble's 37 T hybrid. Future upgrades target 40 T, enhancing fusion confinement (e.g., CFETR tokamak) and particle accelerators.

Challenges remain: Scaling REBCO affordability and quench mitigation. Yet, it heralds energy-efficient paradigms for quantum tech and green energy.Detailed analysis on Interesting Engineering

In summary, CAS's 35.6 T record catalyzes discoveries, urging researchers to engage via rate my professor, higher ed jobs, and career advice.