#superconductivity

Scientists turn common semiconductor into a superconductor

A team has made germanium, a key semiconductor, superconducting by precisely integrating gallium atoms into its crystal lattice.

For decades, researchers have tried to create semiconductor materials that can also act as superconductors -- materials capable of carrying electric current without resistance. Semiconductors, which form the foundation of modern computer chips and solar cells, could operate far faster and more efficiently if they also possessed superconducting abilities. Yet turning materials like silicon and germanium into superconductors has remained a major challenge, largely because it requires maintaining a delicate atomic arrangement that allows electrons to move freely. A global team of scientists has now achieved what once seemed out of reach. In a new study published in Nature Nanotechnology, they report creating a form of germanium that exhibits superconductivity. This means it can conduct electricity with zero resistance, allowing electric currents to circulate endlessly without losing energy. Such behavior could dramatically boost the performance of electronic and quantum devices while reducing power consumption.

For the first time, a quantum computer has successfully measured pairing correlations (quantum signals that show electrons teaming up in pairs), which is essential to helping scientists find one of the holy grails of physics—superconductors that work at room temperature. Superconductors are materials that can conduct electricity with zero resistance, meaning no energy is lost as heat. To work, they need to be cooled to extremely low temperatures, which makes them expensive and impractical for widespread use. Physicists have been trying to tweak their structure to make them work at room temperature, and many believe that understanding and manipulating electron-pairing correlations are key to that breakthrough.

The superflow of two kinds of superconducting electrons (arrows show their velocities) as calculated on supercomputers. Graphic 2 shows superflow of the other subpopulation of electrons on the surface of a vortex cluster. Graphics courtesy of Egor Babaev.

Superconductivity

credit! @helia_boke on twitter i just edited the art but go follow them please! <3

oh my god their art is so good

beidou and kaeya are so hot

basically the “superconducting properties” — levitation and sharp resistivity drops — were entirely due to separate phenomena. from what i can tell, the actual LK-99 material itself is an insulator that exhibits ferromagnetic properties (likely ferrimagnetic since it’s a ceramic but idk the wording may have just been wrong). this allowed for the viral “half-levitation” video, which many ferromagnetics are capable of at room temperature under the right conditions.

the resistivity drops are entirely explained by copper sulfate impurities. at 104.8C, Cu2S undergoes a phase transition, basically a shift in the crystal structure. this new structure is vastly more conductive than the bulk of the LK-99 material, hence the apparent drop in overall resistivity at this temperature.

pure single crystals (no impurities or other defects) of LK-99 were synthesized and showed no signs of this resistivity drop.

“An international collaboration of scientists has created and observed an entirely new class of vortices—the whirling masses of fluid or air.

Led by researchers from Amherst College in the U.S. and the University of East Anglia and Lancaster University in the U.K., their new paper details the first laboratory studies of these "exotic" whirlpools in an ultracold gas of atoms at temperatures as low as tens of billionths of a degree above absolute zero.”

“The unusual nature of the observed whirlpools here, however, is due to symmetries in the quantum gas. One especially fascinating property of physical theories, from cosmology to elementary particles, is the appearance of asymmetric worlds despite perfect underlying symmetries. For example, when water freezes to ice, disordered molecules in a liquid arrange themselves into a periodic array.

The spatial symmetry of a system is often readily identified—for example, a honeycomb has a periodic array of cells with hexagonal symmetry. Although the vortex medium used in this new work is a fluid rather than a solid array, it also possesses an internal set of hidden discrete symmetries. For example, one of the team's ultracold gases had the fourfold symmetry of a square, and another had the tetrahedral symmetry of a four-sided die, familiar to players of fantasy games everywhere.”