Nb-ti alloy is currently the most pressure-resistant superconductor. Recently, the superconductivity of nb-ti alloy superconductor under ultra-high pressure has been systematically studied by the state key laboratory of superconductivity, institute of physics, Chinese academy of sciences/national research center for condensed matter physics, Beijing and Princeton university. It is found that nb-ti alloy maintains zero resistance superconductivity under pressure up to 261.7GPa, which indicates that nb-ti alloy is the most pressure-resistant superconductor known among all superconductors. This pressure is the highest pressure reported for superconductivity. Under this pressure, the transition temperature of nb-ti alloy superconductor superconductivity increased from 9.6k at normal pressure to 19.1k. The experimental results of high voltage reluctance in hefei strong magnetic field showed that its critical magnetic field increased from 15.4t to 19T at pressure of 211GPa and temperature of 1.8k.This is the highest superconducting transition temperature and the highest critical magnetic field found in the transition group metal element alloy superconductor. The results of high pressure XRD of synchrotron radiation of Shanghai light source show that the crystal structure does not change under the pressure of 200 GPa, but its volume is compressed by about 43%. Niob-ti alloy superconductor has been widely used in thousands of known superconductors because of its excellent comprehensive properties. Niobium titanium alloy is a typical binary alloy composed of transition group elements. In the previous study on the high-entropy alloy superconductor (TaNb)0.67(HfZrTi)0.33 composed of multi-element transition group metal elements, it was found that the alloy showed unusually stable superconductivity under ultra-high pressure (pressure over one million atmospheres is ultra-high pressure, and 1 million atmospheres =100 GPa).Since niobium and titanium are the main components of this high entropy alloy, the research on the superconductivity of niobium and titanium alloy under ultra-high pressure can deepen the understanding of the microscopic mechanism of superconductivity of high entropy alloy. The study reveals the made of the element of transition metal alloy superconductor in high pressure the superconductivity can resist deformation and stability of characteristics, it has to do with copper oxides and iron-based superconductors superconductivity sensitivity to the height of the volume change is in stark contrast, and after the transition metal elements also superconductors (valence electronic d in closed shells) of the superconducting transition temperature drop behavior are obviously different according to the volume compression. This study successfully combines experiments on large scientific devices such as high pressure extreme conditions, strong magnetic field and synchrotron radiation, providing a new example for China to use its own large scientific devices to jointly carry out cutting-edge scientific research.
Tag: Nb-ti alloy , Niobium titanium alloy , niobium , titanium
