LINEAR-RESPONSE THEORY OF INTER-QUANTUM-WELL TUNNELING IN A DOUBLE-WELL STRUCTURE WITH INPLANE MAGNETIC-FIELDS

A linear response theory of incoherent tunnelling is presented and com pared to data for the 2D-2D inter-quantum-well conductance for a doubl e-well structure with an external in-plane magnetic field. The tunnell ing conductance, calculated by evaluating the current-current correlat ion function, shows resonances as a function of the magnetic field. Th e widths and heights of the resonance peaks depend sensitively on the intra-well scattering times and temperature. Tunnelling occurs not onl y through the ground-energy sublevels but also through the higher-ener gy sublevels which can be important at high temperatures. Using a diff erential transmission-line model, analytic relationships between the s ource-drain conductance and the tunnelling conductance are derived. Th e theoretical results yield reasonable agreement with the tunnelling c onductance data obtained from this relationship.