Sub-Landau levels in two-dimensional electron system in magnetic field

Considering the role of electron correlation in a two-dimensional (2D) system in strong magnetic field, we investigate the quantum states of two interacting electrons in the quantum Hall effect regime. We introduce sub-Landau levels of the two-electron states by determining their energies and degeneracies. The effects of electron correlation, Zeeman splitting and energy-level broadening on the stability of the electron-pair states are discussed. It is shown that the two electrons in the triplet state with spins aligned parallel to the magnetic field can form a stable electron pair in the 2D system in GaAs/AlGaAs heterojunction. A wavefunction of many electron pairs are presented and compared with the Laughlin wavefunction.