Renormalized Energies of Superfluorescent Bursts from an Electron-Hole Magneto-plasma with High Gain in InGaAs Quantum Wells

TL;DR

This paper investigates the light emission from a 2D electron-hole plasma in a magnetic field, revealing superfluorescent bursts with energies strongly affected by many-body interactions and a persistent excitonic state linked to hidden symmetry.

Contribution

It provides new insights into the renormalized energies and emission dynamics of superfluorescent bursts in magneto-plasmas, highlighting the role of many-body effects and hidden symmetry.

Findings

Superfluorescent bursts are discrete in time and energy.

Emission energies show large red-shifts due to many-body interactions.

The lowest Landau level emission remains excitonic across magnetic fields.

Abstract

We study light emission properties of a population-inverted 2D electron-hole plasma in a quantizing magnetic field. We observe a series of superfluorescent bursts, discrete both in time and energy, corresponding to the cooperative recombination of electron-hole pairs from different Landau levels. The emission energies are strongly renormalized due to many-body interactions among the photogenerated carriers, exhibiting red-shifts as large as 20 meV at 15 T. However, the magnetic field dependence of the lowest Landau level emission line remains excitonic at all magnetic fields. Interestingly, our time-resolved measurements show that this lowest-energy burst occurs only after all upper states become empty, suggesting that this excitonic stability is related to the `hidden symmetry' of 2D magneto-excitons expected in the magnetic quantum limit.