Stimulated emission from the biexciton in a single quantum dot

TL;DR

This paper demonstrates how two optical pulses can generate, entangle, and disentangle electronic states in quantum dots, enabling control over photon emission paths for quantum information applications.

Contribution

It introduces a method to control entanglement and disentanglement in quantum dots using resonant optical pulses, advancing quantum photonics techniques.

Findings

Resonant two-photon excitation creates entangled Bell-like states.

Stimulating emission fully disentangles the two-bit system.

Polarization control directs the photon emission path.

Abstract

Using two optical pulses of different frequencies, we demonstrate entanglement and disentanglement of the electronic states in Stranski-Krastanov quantum dots. Resonant two-photon excitation of the biexciton creates an entangled Bell-like state. The second pulse, being resonant to the exciton-biexciton transition, stimulates the emission from the biexciton and fully disentangles the two-bit system. By setting the polarization of the stimulation pulse, we control the recombination path of the biexciton and, by this, the state of the photons emitted in the decay cascade.