New collective modes in wide quantum wells with in-plane magnetic fields

We theoretically investigate, within the random phase approximation, the collective excitations of symmetric wide quantum wells under in-plane magnetic fields View the MathML source. We find that the View the MathML source field significantly affects the frequencies, (an-)isotropy and types of the plasmon modes. In particular, a high View the MathML source can induce an additional branch of undamped acoustic-like plasmons, which does not exist in single quantum wells without View the MathML source.