Correlations in Electronic Properties of Semiconductor Quantum Wires

Abstract

It is shown that the Raman cross section of semiconductor quantum wires can be completely understood in terms of collective intra- and inter-subband charge and spin modes that propagate with different group velocities. The intensities of the peaks in the cross section are governed by non-analytic, non-Fermi liquid power laws when approaching resonance, with exponents given by the strength of the electron-electron interaction. In addition, results for electron transport through a quasi-one dimensional quantum dot are presented which show that correlations cannot be neglected. However, their signatures depend on which experimental quantity is considered: in the case of linear transport the average of the interaction is measured including the quantum wires to which the quantum dot is connected. In non-linear transport spectroscopy, the interaction is probed at the position of the quantum dot. It is also concluded that in quasi-one dimensional quantum dots the excitations with the lowest energies are due to spin modes.