Good news! The holy grail of superconductors! When will they become reality?
It still seems a long way to go unless a proverbial light bulb goes off or some discovery by accident!
"A new superconducting compound offers a bridge to more practical superconductors with a potentially attractive range of applications, according to new research. And the new material’s strange magnetic behavior recalls classic superconductors of decades ago—but this time in a material that’s already demonstrated its near-room-temperature bona fides.
Lanthanum hydrides—which combine atoms of the rare earth metal lanthanum with atoms of hydrogen—contain a range of superconducting materials of varying properties. One noteworthy material is lanthanum decahydride (LaH10), which boasts the world’s highest accepted superconducting transition temperature, at –23 °C. (The catch is that to achieve this feat, lanthanum decahydride must be subjected to 200 billion pascals of pressure.)
If lanthanum hydrides are newcomers to superconductivity, cuprates are their old, establishment counterparts. Since the 1980s, scientists have studied cuprates like yttrium barium copper oxide (YBCO) and bismuth strontium calcium copper oxide (BSCCO) with critical temperatures above the –196 °C boiling point of liquid nitrogen—and which, crucially, don’t need unearthly pressures. ..."
Lanthanum hydrides—which combine atoms of the rare earth metal lanthanum with atoms of hydrogen—contain a range of superconducting materials of varying properties. One noteworthy material is lanthanum decahydride (LaH10), which boasts the world’s highest accepted superconducting transition temperature, at –23 °C. (The catch is that to achieve this feat, lanthanum decahydride must be subjected to 200 billion pascals of pressure.)
Now a different lanthanum hydride (La4H23) has revealed similar if not quite equally impressive superconductivity stats. (Its transition temperature is –168 °C at 122 billion Pa.) However, the new lanthanum hydride also has revealingly peculiar magnetic properties that suggest an unexpected family resemblance to the superstar of the superconductivity world, cuprates.
From the abstract:
"Hydride superconductors continue to fascinate the communities of condensed matter physics and material sciences because they host the promising room-temperature superconductivity. The current research has been concentrated on the new hydride superconductors with the enhancement of the superconducting transition temperature (Tc). The multiple extreme conditions (high pressure/temperature and magnetic field) will introduce new insights on the hydride superconductors. The study of transport properties under very high magnetic fields facilitates the understanding of the superconductivity in the conventional hydride superconductors. In the present work, we report experimental evidence of an unusual metal state in a newly synthesized cubic A15-type La4H23 that exhibits superconductivity with a Tc reaching 105 K at 118 GPa. A large negative magnetoresistance is observed for strong pulsed magnetic fields in the non-superconducting state below 40 K. Moreover, we construct the full magnetic phase diagram of La4H23 up to 68 T at high pressure. The present work reveals anomalous electronic structural properties of A15-La4H23 under high magnetic fields, therefore holding great importance for advancing the understanding of quantum transport behaviors in hydride superconductors."
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