The frequency degree of freedom of single photons provides a large dimensional and robust quantum encoding. The frequency is a continuous degree of freedom that can be used for defining a continuous encoding [1], but it can be also discretized to define frequency qudits or qubits [2,3]. The implementation of logical operations manipulating the spectral degree of freedom of single photons is necessary for using such a degree of freedom in quantum information protocols, from quantum metrology to communication and computation.

To tackle this goal, the internship’s student will investigate theoretical methods for implementing realistic frequency logical operations by probabilistic and deterministic optical schemes. In particular, the student will investigate tools for manipulating frequency combs at the single photon level, and optical gates that entangle the frequency degree of freedom of single photons.

We are looking for a candidate with skills and interest in theoretical quantum optics and information, interested in proposing experiments achievable in the near term. This internship will be the starting point of an experimental collaboration with an international network.

References:
[1] N. Fabre, A. Keller, and P. Milman, Time and Frequency as Quantum Continuous Variables, Phys. Rev. A 105, 052429 (2022).
[2] N. Fabre et al., Generation of a Time-Frequency Grid State with Integrated Biphoton Frequency Combs, Phys. Rev. A 102, 012607 (2020).
[3] S. Francesconi, F. Baboux, A. Raymond, N. Fabre, G. Boucher, A. Lemaître, P. Milman, M. I. Amanti, and S. Ducci, Engineering Two-Photon Wavefunction and Exchange Statistics in a Semiconductor Chip, Optica 7, 316 (2020).

Nicolas Fabre
Télécom Paris, Institut Polytechnique de Paris, 91120 Palaiseau France nicolas.fabre@telecom-paris.fr