Missions

In recent years, we have demonstrated the possibility of deterministically generating photonic graph states by exploiting the entanglement between the spin state of a carrier trapped in a quantum dot and the polarization of the photons successively emitted by the dot. We are now able to entangle around ten photons in this way—a key capability for the next generation of quantum processors that we are developing in collaboration with the startup Quandela, within the joint laboratory between C2N and QDLight, and as part of the European project EPIQUE.

The postdoctoral researcher will contribute to this effort by implementing advanced excitation protocols for quantum dots. These protocols aim to achieve near-unit occupation of the excited state of the quantum emitter, while preserving access to polarization selection rules.

Activities

Quantum optics measurements on single quantum emitters
Writing of scientific reports and journal articles
Participation in the project's scientific meetings
Supervision of students in the team during daily experimental activities

Skills

Advanced expertise in experimental quantum optics
Strong knowledge of the physics of semiconductor quantum dots
Background in light–matter interaction and cavity quantum electrodynamics

Work Context

Over the past ten years, our team at C2N has developed quantum light sources based on artificial atoms known as semiconductor quantum dots. These quantum emitters, carefully integrated into optical cavities, generate indistinguishable single photons with high efficiency. Since 2017, these sources—enabling a significant expansion of the possibilities for optical quantum computing—have been commercialized internationally (Australia, Italy, Austria, the Netherlands, Germany, and beyond) by the company Quandela (www.quandela.com
). Using such sources, the first on-chip photon manipulation protocols have already been demonstrated with about ten photons.

To move towards scalability and error correction, we are adopting a measurement-based computing paradigm. This model assumes that it is possible to generate light states in which a large number of photons are redundantly entangled. The realization of a gate operation on one qubit, followed by its measurement, influences the other qubits with which it was entangled, thereby effectively performing an operation on them. The key challenge is therefore to generate these special classes of light states, known as graph states, in an efficient manner.

The position is located in a sector under the protection of scientific and technical potential (PPST), and therefore requires, in accordance with the regulations, that your arrival is authorized by the competent authority of the MESR.

Constraints and risks

Optical laboratory work with cryogenics