A room temperature superconductor is theoretically possible, but no one has made one yet. The closest anyone has come is a lanthanum hydride compound that superconducts at about minus 23 degrees Celsius (roughly minus 9 degrees Fahrenheit), which is cold but remarkably close to everyday temperatures. The catch: it only works under pressures exceeding 1.5 million times atmospheric pressure, squeezed between the tips of two tiny diamonds. The real goal, a material that superconducts at room temperature and normal pressure, remains one of the most sought-after breakthroughs in physics.
What Superconductivity Actually Requires
A superconductor does two things. First, it conducts electricity with absolutely zero resistance, meaning current flows through it without losing any energy to heat. Second, it expels magnetic fields from its interior, a phenomenon called the Meissner effect, which is why superconductors can levitate magnets. Both properties must be present. A material that simply has very low resistance isn’t a superconductor, and a material that repels magnets for other reasons (like being ferromagnetic) isn’t one either.
These two tests, zero electrical resistance and magnetic field expulsion, are the gold standard for confirming superconductivity. Any claim of a new superconductor must demonstrate both, measured carefully and reproduced by independent labs. This verification standard has tripped up several high-profile claims in recent years.
How Close We’ve Gotten
The history of superconductivity is a story of slowly pushing temperatures upward. When the phenomenon was first discovered in mercury in 1911, the transition temperature was just 4.2 Kelvin, roughly minus 269 degrees Celsius. For 75 years, progress was glacial. By 1986, the record still sat below 23 Kelvin.
Then came a dramatic leap. In 1986, researchers at IBM in Switzerland found that a ceramic compound containing lanthanum, barium, copper, and oxygen became superconducting at 30 Kelvin. Within a year, substituting yttrium for lanthanum pushed the temperature above 90 Kelvin. By 1993, a mercury-based copper oxide compound reached 135 Kelvin (minus 138 degrees Celsius), the highest transition temperature ever confirmed at normal atmospheric pressure. That record has stood for over three decades.
The real temperature leaps came from a different approach: crushing hydrogen-rich materials under extreme pressure. In 2019, a team from the Max Planck Institute and the University of Chicago demonstrated superconductivity at 250 Kelvin (minus 23 degrees Celsius) in lanthanum hydride, but the sample was only a few microns across and required pressures between 150 and 170 gigapascals. Theoretical calculations suggest that at around 200 gigapascals, the same family of materials could superconduct near 280 Kelvin, which is about 7 degrees Celsius. That’s practically room temperature, but the pressure needed is roughly what you’d find at Earth’s core.
What Theory Says About the Limit
For decades, many physicists assumed that conventional superconductivity had a hard ceiling around 30 to 40 Kelvin, based on a formula developed in the late 1960s. This so-called McMillan limit became almost folklore in the field. But that limit was specific to certain metallic alloys, not a fundamental boundary of the underlying physics.
The broader theoretical framework, known as BCS theory (after the three physicists who developed it), actually permits superconducting temperatures up to about 400 Kelvin under the right conditions. Recent theoretical work confirms that 300 Kelvin, a comfortable room temperature, is mathematically achievable within BCS theory at ambient pressure. The question is whether a real material can hit those conditions.
Carbon-based compounds are currently considered the most promising candidate group for reaching room temperature superconductivity at normal pressure within this theoretical framework. Carbon’s properties, particularly the way its bonds vibrate at high frequencies, create favorable conditions for the electron pairing that drives superconductivity. No carbon-based material has come close to room temperature yet, but the theoretical door is open.
High-Profile Failures and Why They Matter
The pursuit of room temperature superconductivity has produced some painful false starts. In 2023, physicist Ranga Dias published a paper in Nature claiming near-ambient superconductivity in a nitrogen-doped lutetium hydride, sometimes called “Reddmatter.” The paper was retracted after an investigation found credible, substantial, and unresolved concerns about the reliability of the electrical resistance data. Dias and some co-authors did not state whether they agreed with the retraction.
That same year, a team in South Korea announced LK-99, a lead-based compound they claimed was a room temperature, ambient pressure superconductor. The announcement went viral, with labs around the world racing to replicate the results. The scientific consensus that eventually emerged was clear: LK-99 does not exhibit superconducting properties. The magnetic behavior that had generated excitement turned out to stem from impurities in the material, not from superconductivity. Debates about LK-99 continued online for over two years despite that consensus.
These episodes highlight why the verification standards matter so much. Superconductivity is rare and extraordinary, and extraordinary claims need zero resistance, the Meissner effect, and independent replication. Partial evidence, no matter how exciting, isn’t enough.
How AI Is Changing the Search
One reason for cautious optimism is that the search for new superconducting materials is accelerating dramatically. Researchers have developed AI-powered pipelines that can screen millions of candidate materials in a fraction of the time it would take to test them physically. A recent workflow used a specialized neural network to predict superconducting temperatures, achieving a mean error of less than 1 Kelvin compared to traditional computational methods. More impressively, the model correctly identified 99.4% of non-superconducting materials, which means researchers can quickly eliminate dead ends.
In one demonstration, this pipeline narrowed over 1.3 million candidate structures down to 741 compounds that were both physically stable and predicted to superconduct above 5 Kelvin. That’s still far from room temperature, but the approach dramatically expands the number of materials scientists can evaluate. The hope is that somewhere in the vast space of possible compounds, combinations no one has thought to try yet could have much higher transition temperatures.
What Would Have to Happen
There are essentially two paths to a room temperature superconductor. The first is finding a way to stabilize the hydrogen-rich compounds that already superconduct near room temperature, but without the crushing pressures they currently require. Some researchers are exploring chemical “pre-compression,” using the structure of surrounding atoms to mimic the effect of extreme pressure. Progress here has been slow.
The second path is discovering an entirely new class of materials that superconducts at room temperature and normal pressure through a mechanism that may not yet be fully understood. The copper oxide superconductors discovered in the 1980s operate through a pairing mechanism that physicists still debate, so there’s precedent for materials that break existing theoretical expectations.
Neither path has a guaranteed timeline. The gap between the best ambient-pressure superconductor (135 Kelvin, set in 1993) and room temperature (roughly 293 Kelvin) is enormous. But theory doesn’t forbid it, the search tools are better than ever, and the pressurized hydrides prove that superconductivity itself can survive at these temperatures. The barrier is materials engineering, not physics.