  The scalability of quantum dot based non-classical light sources relies on
the control over their dissimilar emission energies. Electric fields offer a
promising route to tune the quantum dot emission energy through the
quantum-confined Stark effect. However, electric fields have been mostly used
for tuning the energy of single-photon emission from quantum dots, while
electrical control over the energy of entangled-photon emission, which is
crucial for building a solid-state quantum repeater using indistinguishable
entangled photons, has not been realized yet. Here, we present a method to
achieve electrical control over the energy of entangled-photon emission from
quantum dots. The device consists of an electrically-tunable quantum diode
integrated onto a piezoactuator. We find that, through application of a
vertical electric field, the critical uniaxial stress used to eliminate the
fine-structure-splitting of quantum dots can be linearly tuned. This allows
realization of a triggered source of energy-tunable entangled-photon emission,
an important step towards a solid-state quantum repeater application.
