Electron-electron interactions and two-dimensional–two-dimensional tunneling

We derive and evaluate expressions for the dc tunneling conductance between interacting two-dimensional electron systems at nonzero temperature. The possibility of using the dependence of the tunneling conductance on voltage and temperature to determine the temperature-dependent electron-electron scattering rate at the Fermi energy is discussed. The finite electronic lifetime produced by electron-electron interactions is calculated as a function of temperature for quasiparticles near the Fermi circle. Vertex corrections to the random-phase approximation substantially increase the electronic scattering rate. Our results are in an excellent quantitative agreement with experiment. {} 1996 The American Physical Society.