We report on the exact space-and-time-dependent dynamics of a correlated electron-hole pair in non-perturbative in-plane external fields in semiconductor layered heterostructures.
Exact time-dependent Schrödinger propagation for tens of picoseconds of this two-body system has been performed in a wide range of scattering potentials, including ramps, wells, barriers, quantum point contacts, anti-dots, which model gate-generated potentials in typical semiconductor nanostructures. Since gates produce an electrostatic field of opposite sign for the two particles, the scattering substantially shakes internal degrees of freedom, and generally entangles the centre-of-mass (c.m.) and relative motions. This induces complex transient phenomena, and leads to strong renormalization of, e.g., transmission resonant energies and tunneling probabilities at asymptotic times, as well as diffraction patterns which are not expected in the commonly adopted, simplified picture where the electron-hole pair is viewed as a single-particle.
Common mean-field approaches are proven to fail in reproducing this phenomenology. We show that internal virtual transition are the fundamental missing ingredient, and can be restored by a properly-designed local self-energy potential acting on the the c.m.
This leads to a very good agreement with exact calculations at the very reduced numerical cost of mean-field calculations.
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