For decades, room-temperature superconductivity has been one of physics’ ultimate goals, a Holy Grail-like objective that seems to keep drifting within realization yet always stubbornly out of reach. Various materials, theories, and techniques have been proposed and explored in search of this objective, but its realization has remained elusive. Yet recent experimental work on hydrogen-rich materials at high pressures is finally opening the pathway to practical superconductivity and its vast potential. Russell Hemley, a materials chemist at George Washington University in Washington, D.C., first announced evidence of superconductivity at 260 K in May, 2018, and then hints of an even higher 280 K transition in August of that year. Now Hemley, along with a team of researchers from The George Washington University and the Carnegie Institution for Science synthesized several lanthanum superhydride materials that demonstrated the first experimental evidence of superconductivity at near room temperature, and with colleagues from Argonne National Laboratory characterized them at the U.S. Department of Energy’s Advanced Photon Source (APS).
Image: The structure of LaH10 with the sample and the four platinum leads at 180 GPa. The confirmation with in situ x-ray diffraction after laser heating shows the drop in resistivity starting at around 265 K in one of the samples synthesized. The confirmation of the structure was determined from the powder diffraction pattern shown in the lower panel. The data was obtained at HP-CAT beamline 16-ID-B at the APS.