Giant Proximity Effect Enhances High-Temperature Superconductivity
Sandwiched superconductors engineered to function at higher temperatures could be used in new ultra-fast superconducting electronics
Story content courtesy of the U.S. Department of Energy’s Brookhaven National Laboratory, US
Scientists at the U.S. Department of Energy's Brookhaven National Laboratory (BNL), collaborating with scientists from the Paul Scherrer Institute (PSI) and the University of Zürich in Switzerland, have found that sandwiching a barrier layer between two superconductors can make it superconducting at significantly higher temperatures. Finding ways to raise the temperature further, such as the layering approach described by the research team, could lead to the realization of such applications as low-power consumption, ultra-fast superconducting electronic devices.
"More recently, we have observed a mysterious 'Giant Proximity Effect' in copper-oxide materials - cuprates - when supercurrent flows through much thicker barriers," said Brookhaven physicist Ivan Bozovic, co-author of the research paper. Because thicker layers are easier to fabricate and work with, taking advantage of the Giant Proximity Effect could make it much easier to achieve on-chip device uniformity - the requirement that all devices on an electronic chip have similar parameters.
By mapping the magnetic fields for each structure, the scientists observed the Giant Proximity Effect and found that a thick barrier of superconductor with a Tc of 5 Kelvin could transmit supercurrent at a temperature four times higher, if it is sandwiched between two superconductors with a Tc of 40 Kelvin.
This research was supported by DOE's Office of Science.