Building structures in a sheet of superconducting material could
lead to new devices for processing information. Researchers now
report in Physical Review Letters that the superconductivity of
an ultrathin layer can be dramatically suppressed by
electrically polarizing an atomically matched layer on top of
it. The team was also able to suppress superconductivity in an
array of nanometer-sized dots without affecting the material
between the dots, raising hopes for new ways to pattern
superconducting circuits. The zero-resistance state of a
superconductor appears below a critical temperature .
Researchers would like to manipulate this transition temperature
selectively in circuits, or even suppress superconductivity
entirely in some places, to make new kinds of devices. They can
weaken the superconductivity and lower by reducing the number of
charge carriers (either electrons or positively-charged holes,
depending on the material). One way to lower the carrier
concentration is to expose a thin layer of the mate