Gate controlled coupling of intersubband plasmons

摘要: The optical response of a heavily doped quantum well, with two occupied subbands, has been investigated as function the electronic density. It is shown that optically active transitions are mutually coupled by dipole-dipole Coulomb interaction, which strongly renormalizes their absorption amplitude. In order to demonstrate this effect, we have measured set spectra on device in density can be tuned application gate voltage. Our results show correctly described only taking into account coupling between transitions. As consequence, dipoles originating from intersubband not independent, but rather oscillators an adjustable strength.