Infra-red Tunneling Absorption in Semiconductor Double Quantum Wells in Tilted Magnetic Fields

JAM 0 6 1997 ABSTRACT C D A F ~ 6 /xQ--SO 0 ST I Using a linear response theory, interwell-tunneling absorption is calculated in a double-quanturn-well structure with a wide center barrier in tilted magnetic fields. Tunneling absorption of infra-red photons occurs between the ground sublevels of the two quantum wells, with an energy difference that is tunable. In zero magnetic field, the absorption intensity decreases significantly as the linewidth increases with temperature. The absorption also depends strongly on the carrier densities of the wells. In magnetic fields, both the in-plane and perpendicular components of the field sensitively control and tune the absorption lineshape in very different ways, affecting the absorption threshold, the resonance energy of absorption, and the linewidth.