Superconducting, Magnetic & Photonic Materials

c. 600 BC · about 2,600 years ago

Thales of Miletus discussed the attractive properties of lodestone

The Greek philosopher's discussion is among the earliest surviving Western accounts of magnetism, with the term magnet later derived from Magnesia, the region where the ore was found.

4th century BC · about 2,400 years ago

Chinese texts including the Guanzi gave the earliest known descriptions of lodestone's magnetic attraction

Early Chinese philosophical and technical texts describe lodestone's ability to attract iron, predating similar observations recorded in the Mediterranean world by several centuries.

1088 · 938 years ago

Shen Kuo gave the first clear description of a navigational compass

The Song dynasty scholar described a magnetised needle compass used for navigation, along with an early account of magnetic declination, in his Dream Pool Essays.

1824 · 202 years ago

William Sturgeon built the first practical electromagnet

Sturgeon wound insulated wire around an iron core to create a magnet capable of lifting many times its own weight, moving magnetism from a natural curiosity to an engineerable technology.

April 1911 · 115 years ago

Heike Kamerlingh Onnes discovered superconductivity in mercury

Working at Leiden and studying the resistance of mercury at cryogenic temperatures using newly produced liquid helium as a refrigerant, Onnes observed that electrical resistance vanished abruptly at 4.2 K. The precise date and circumstances were only reconstructed a century later when his notebook was found. He received the 1913 Nobel Prize in Physics for his low-temperature work, including the production of liquid helium.

1913 · 113 years ago

Researchers found superconductivity in tin and lead at 3.8 K and 7 K

Following the mercury result, superconductivity was identified in further elemental metals, showing the phenomenon was general rather than peculiar to mercury. This widened the search for practical superconducting materials.

1933 · 93 years ago

Walther Meissner and Robert Ochsenfeld discovered that superconductors expel magnetic fields

The German physicists found that superconductors actively expel magnetic fields from their interior, a defining property distinct from merely having zero electrical resistance and essential to later levitation applications.

1935 · 91 years ago

Fritz and Heinz London formulated the London constitutive equations

The brothers showed that the Meissner effect follows from minimising the electromagnetic free energy carried by the superconducting current. Their classical phenomenological model gave the first quantitative account of how magnetic field decays with depth inside a superconductor, defining the London penetration depth.

1941 · 85 years ago

Researchers found niobium nitride superconducting at 16 K

Niobium nitride raised the known critical temperature substantially above that of the elemental superconductors. It marked the beginning of niobium-based compounds as the most promising family for practical superconducting technology.

1950 · 76 years ago

Landau and Ginzburg devised the phenomenological Ginzburg–Landau theory

Combining Landau's theory of second-order phase transitions with a Schrödinger-like wave equation, the theory successfully explained the macroscopic properties of superconductors. Abrikosov later used it to predict the division into Type I and Type II superconductors, the latter underpinning all high-field magnet technology. Abrikosov and Ginzburg shared the 2003 Nobel Prize for this work.

1950 · 76 years ago

Maxwell and Reynolds et al. found the critical temperature depends on isotopic mass

The isotope effect showed that the transition temperature varied with the mass of the constituent element's isotopes. This pointed directly to the electron–phonon interaction as the microscopic mechanism of superconductivity, guiding theorists towards BCS theory.

1954 · 72 years ago

Dudley Allen Buck invented the cryotron, the first practical superconducting application

The cryotron combined two superconductors with very different critical magnetic fields to make a fast, simple switch for computer elements. It was the first practical application of superconductivity, and in the 1950s and 1960s cryotron switches were used to build experimental digital computers.

1955 · 71 years ago

G. B. Yntema built a 0.7-tesla superconducting electromagnet with niobium windings

Onnes had attempted superconducting electromagnet windings soon after 1911 but found modest fields destroyed superconductivity in the materials available. Yntema's small iron-core magnet with niobium wire windings was the first success, opening the path to superconducting magnet engineering.

1957 · 69 years ago

Bardeen, Cooper and Schrieffer proposed the microscopic BCS theory of superconductivity

BCS theory explained the superconducting current as a superfluid of Cooper pairs — electron pairs bound through the exchange of phonons. It provided the complete microscopic account of conventional superconductivity and earned its authors the 1972 Nobel Prize.

1958–59 · 68 years ago

N. N. Bogolyubov and Lev Gor'kov placed BCS theory on a firmer footing and linked it to Ginzburg–Landau

Bogolyubov showed in 1958 that the variationally derived BCS wavefunction could be obtained by a canonical transformation of the electronic Hamiltonian. In 1959 Gor'kov demonstrated that BCS theory reduces to Ginzburg–Landau theory near the critical temperature, unifying the microscopic and phenomenological pictures.

1961 · 65 years ago

Kunzler, Buehler, Hsu and Wernick discovered niobium–tin's huge current density in high field

At 4.2 K the compound carried over 100,000 amperes per square centimetre in an 8.8-tesla field. Though brittle and hard to fabricate, niobium–tin proved capable of generating fields as high as 20 tesla, making high-field superconducting magnets feasible.

1962 · 64 years ago

T. G. Berlincourt and R. R. Hake discovered ductile niobium–titanium alloys usable to 10 tesla

Commercial production of niobium–titanium supermagnet wire commenced immediately at Westinghouse Electric Corporation and Wah Chang Corporation. Despite weaker superconducting properties than niobium–tin, its ductility and ease of fabrication made it the workhorse magnet material for MRI scanners and particle accelerator magnets.

1962 · 64 years ago

Brian Josephson predicted the Josephson effect of supercurrent tunnelling

Josephson predicted theoretically that a supercurrent can flow between two superconductors separated by a thin insulating layer. The effect underpins SQUID magnetometers and the most accurate measurements of the magnetic flux quantum, and hence of the Planck constant. He received the Nobel Prize in 1973.

1980s · 46 years ago

Theorists showed the superconducting transition order using disorder field theory

Using a theory in which vortex lines play the major role, it was shown that the transition is second order in the Type II regime and first order in the Type I regime, separated by a tricritical point. This refined earlier 1970s calculations suggesting a weakly first-order transition due to long-range electromagnetic fluctuations.

1984 · 42 years ago

General Motors and Sumitomo Special Metals independently developed neodymium-iron-boron magnets

Researchers in the United States and Japan developed the strongest permanent magnets yet made, now standard in electric motors, wind turbines and hard disk drives.

April 2026 · 4 months ago

China expanded export licensing controls on rare earth magnets

Additional categories of processed rare earth elements and finished neodymium magnets were brought under export licensing, tightening a supply-chain lever China had used with increasing frequency amid trade tensions with the United States and its partners.

• Automakers and defence contractors reported renewed difficulty securing licences

March 2026 · 5 months ago

Japan increased investment in non-Chinese rare earth magnet supply chains

Japanese trading houses and manufacturers expanded financial backing for rare earth processing capacity in Australia and elsewhere, continuing a decade-long effort to reduce dependence on Chinese-processed magnet materials.

February 2026 · 6 months ago

India advanced its national rare earth magnet mission

Funding under the government programme aimed to establish domestic processing and neodymium-iron-boron magnet production, reducing near-total reliance on imported magnets for electric motors and defence systems.

January 2026 · 7 months ago

South Korea's KSTAR tokamak reported a new sustained high-confinement plasma duration

The superconducting tokamak extended the length of time it could sustain high-temperature, high-confinement plasma, building on a series of incremental records that support the design of future fusion reactors.

December 2025 · 8 months ago

Commonwealth Fusion Systems completed a major construction milestone on its SPARC tokamak

Assembly of the Massachusetts-based fusion company's high-temperature superconducting magnet tokamak advanced toward a planned first-plasma milestone, continuing to attract private investment on the strength of its compact magnet design.

November 2025 · 9 months ago

Lynas Rare Earths expanded magnet-grade rare earth separation capacity

The Australian company increased processing capacity at its Malaysian and domestic facilities, adding to the small number of rare earth separation plants operating outside China.

• Automakers in Japan and Europe signed offtake agreements for the expanded output

October 2025 · 10 months ago

Chinese engineers unveiled a new high-speed maglev test vehicle

The prototype, tested on a dedicated track, targeted commercial speeds well above those of conventional high-speed rail, extending China's decade-long programme of superconducting and electromagnetic maglev development.

2025 · last year

Tokamak Energy reported progress with its compact spherical tokamak using high-temperature superconducting magnets

The British fusion company advanced testing of its magnet technology, part of a wave of privately funded fusion ventures betting that high-temperature superconducting magnets can make reactors smaller and cheaper than earlier designs.

Mid-2025 · last year

ITER's international partners reported a further delay to the project's first-plasma timeline

Continued technical issues with reactor components, including magnet system integration, pushed back the target date for first plasma at the fusion research project, jointly funded by partners including the EU, China, India and the United States.

• The central solenoid magnet system underwent additional testing after component issues

2024 · 2 years ago

China's EAST tokamak achieved a record-length steady-state high-confinement plasma run

The facility sustained high-confinement plasma for over 1,000 seconds, a new record for steady-state operation and a significant data point for the physics underpinning future fusion power plants.

2021–22 · 5 years ago

Researchers extended 2D superconductivity to trilayer graphene devices

A twisted three-layer graphene device was shown to superconduct at about 2.8 K in 2021, followed by an untwisted trilayer device at 1–2 K in 2022. The untwisted device proved tunable, allowing rapid testing of an unprecedented number of configurations for superconductivity, with applications in quantum computing.

2020 · 6 years ago

Researchers created the first superconducting Bose–Einstein condensate

The first development and study of a superconducting BEC suggested a smooth transition between the BEC and Bardeen-Cooper-Schrieffer regimes. It linked ultracold atomic physics with conventional superconducting pairing theory.

2018 · 8 years ago

Researchers achieved superconductivity in twisted bilayer graphene

A bilayer graphene sheet twisted by 1.1 degrees superconducted at about 1.7 K, the first success with two-dimensional materials. The moiré superlattice slows electrons enough for their collective interactions to drive Cooper pairing, creating a highly tunable platform for studying superconductivity.

2015 · 11 years ago

Researchers achieved a record conventional critical temperature of 203 K in H2S under pressure

Hydrogen sulphide was found to superconduct at 203 K, the highest critical temperature recorded for a conventional superconductor. The result required pressures of approximately 90 gigapascals, limiting practical use but reframing the search for room-temperature superconductivity.

2015 · 11 years ago

JR Central's L0 series maglev set the world speed record for a passenger rail vehicle

The trainset, levitated and propelled by superconducting magnets, reached 603 kilometres per hour on the Yamanashi test track, the fastest speed ever recorded by a passenger rail vehicle.

2014 · 12 years ago

Conectus, a European superconductivity consortium estimated €5 billion of activity depending on superconductivity

The consortium estimated that global economic activity for which superconductivity was indispensable amounted to about five billion euros. MRI systems accounted for roughly 80 per cent of that total, showing medical imaging as the dominant commercial market for superconducting magnets.

2008 · 18 years ago

Theorists proposed a superinsulator state from the superconducting mechanism

It was suggested that the same mechanism producing superconductivity could yield materials with almost infinite electrical resistance. The proposal extended the theoretical reach of pairing physics beyond zero-resistance behaviour.

1995–2024 · 31 years ago

A superconducting gravimeter in Belgium sustained a persistent current for over 28 years

Currents injected into superconducting coils persisted from August 1995 until March 2024 without a power source. The demonstration provided a practical measure of the effectively infinite lifetime of supercurrents, experimentally bounded at over 100,000 years.

1986–87 · 40 years ago

Ching-Wu Chu raised the critical temperature to 92 K by making YBCO

Replacing lanthanum with yttrium in the cuprate structure lifted the transition temperature to 92 K, above the 77 K boiling point of liquid nitrogen. Cheap liquid nitrogen cooling made a wide range of superconducting experiments and applications practical for the first time.

1986 · 40 years ago

Georg Bednorz and Alex Müller discovered high-temperature superconductivity

Working at IBM's Zurich laboratory, Bednorz and Müller found that certain cuprate-perovskite ceramics superconduct above 35 K, a transition temperature theoretically impossible for a conventional superconductor. The materials were termed high-temperature superconductors, opening an entirely new class of materials and earning the pair the 1987 Nobel Prize in Physics.

• A team including Ching-Wu Chu identified a compound superconducting above the boiling point of liquid nitrogen