Magnetic bubble

цилиндрический магнитный домен, ЦМД

Англо-русский политехнический словарь

Magnetic bubble

noun a tiny movable magnetized cylindrical volume in a thin magnetic material that along with other like volumes can be used to represent a bit of information (as in a computer)

Энциклопедический словарь Мерриама-Вебстера