Individual charge-trapping dislocations in an ionic insulator

Insulating oxide materials find widespread technological applications where how their inside dislocations behave are known to influence or control performance. Here we demonstrate, by first-principles calculations on MgO, that individual dislocations can trap charges within empty space around their cores in an unusual pipelike way, regardless of whether the charges are produced via external excitation or impurity doping. Such effect of dislocations is crucial for many applied physics issues as well as opens up an avenue for exploring functional devices based on the confined charges.