CORRELATION-EFFECTS IN QUANTUM DOTS IN MAGNETIC-FIELDS

Tunneling rates into quantum dots in the presence of a magnetic held B are discussed by analyzing N-electron wave functions. Exact diagonali zations of the total Hamiltonian for up to 20 electrons are performed. When B is varied, transitions between uncorrelated states occur throu gh strongly correlated states. Correlated states are responsible for t he strong reduction of tunneling rates in the transition region. At hi gh fields the lowest energy state within each subspace of given angula r momentum is a magnetoexciton that can be generated by a novel set of operators. Correlation produces, once again, a reduction of tunneling rates. The spectral function presents damped oscillations as a functi on of the energy that can be described by the operators creating magne toexcitons.