EDMs, i.e. electric dipole moments of electrons, neutrons or nuclei are sensitive probes for new physics beyond the Standard Model of particle physics. In the present project, we propose to measure the EDM of those systems embedded in a cryogenic solid matrix of inert gas or hydrogen. Matrices offer unprecedented sample sizes while maintaining characteristics of an atomic physics experiment, such as the possibility of manipulation by lasers. An EDM experiment on molecules in inert gas matrices has the potential to reach a statistical sensitivity of the order of 1e–36 e cm; a value beyond that of any other proposed technique. With this project, in a strong collaboration between experimental (LAC, ISMO,LPL) and theoretical (CIMAP) groups, we first aim at performing a detailed investigation of all limiting effects (mainly the ones limiting the optical pumping performance and coherence time) using Cs atoms. This should provide a first proof of principle EDM measurement and set the ground for precise study of systematic effects which will allow EDMMA to reach unprecedented precision

Fast amplitude and phase modulation is essential for a plethora of applications in photonics, including laser amplitude/frequency stabilisation, coherent detection, optical communications, spectroscopy, gas sensing etc. In the mid-infrared (MIR) wavelength range (3-12um) broadband MDs are missing, hampering the progress of MIR photonics. In this project we aim at demonstrating two types of power efficient and broadband (up to ~40GHz bandwidth) integrated MIR amplitude- and phase-MDs, suitable for industrial production, that will be capable of addressing the needs of emerging MIR photonics applications. The frequency response of these devices (optimised in the 9.5-10.5um wavelength range) will be fully characterised using an in-house fabricated ultra-broadband (>70GHz) detector and a VNA analyser. Finally, the potential of the MDs for spectroscopy/gas sensing applications will be demonstrated by setting up an original high resolution-spectroscopy experiment.

The question of dissipation in quantum many-body systems is a subject of considerable interest, for fundamental reasons – associated with the understanding of how many-body quantum correlations survive in presence of decoherence – and for the development of realistic platforms for quantum technologies. In parallel to the question of how dissipation may harm quantum coherences, it has also been suggested to use dissipation in order to create interesting many-body systems – a concept that generalizes that of optical pumping. The idea of dissipative-state engineering is to introduce a controlled coupling to an environment that can induce correlations or symmetries, and can produce or stabilize quantum correlated states. Our project is to combine experimental and theoretical efforts, to explore the dissipative engineering of collective spin states that are relevant for quantum sensing and quantum simulation. The platform is an ultracold-atom quantum simulator that realizes the Hubbard Hamiltonian in an optical lattice. We will use strontium 87 atoms, a fermionic spin-9/2 species exhibiting a SU(N) spin symmetry – corresponding to an invariance of the system when permuting any two spin states within N spin states, where the number N can be controlled at will from 2 to 10. Based on prior theoretical work, two-body losses in SU(2) or SU(3) systems provide an opportunity to engineer highly-entangled generalized Dicke states, that are of interest to quantum sensing. Our project is to first experimentally verify this possibility, and then study its generalization for SU(N>3) systems, both from the experimental and the theoretical standpoint. For this we will make use of an exceptional tunability that is offered by the narrow lines of strontium atoms, that are of interest to the precision measurement community. In practice, we will use these transitions to engineer losses via photo-association. By simply tuning the magnetic field, these losses can be made either spin-sensitive or spin insensitive, which allows full control over both the strength and the spin selectivity of dissipation. We will also develop a new scheme to drive at will two-body or three-body losses. Due to the local character of losses and the anti-symmetric nature of the few-body wavefunction, those two- and three- body losses specifically target respectively SU(2) or SU(3) singlet states. These capacities will enable an investigation of dissipative quantum dynamics with a full control of the symmetry of the Hamiltonian, from SU(2) to SU(10), and of the symmetry of dissipation. When losses are low, we generally expect the system to be driven into stationary states that favour triplet correlations. We will study these states, and perform Ramsey sequences to characterize their metrological quality. Furthermore, we will also perform the first study of dynamics of SU(N) lattice gases in the regime of strong dissipation, where the quantum Zeno effect is at play, so that long-lived, strongly correlated many-body states should emerge, with similarities to those that arise in the quantum t-J model at low energy. In both regimes, we will study the robustness of dynamics and of the stationary or metastable states in presence of inhomogeneities, in order to assess the practical usefulness of the highly symmetric novel quantum many-body states that can spontaneously arise in these systems. Therefore, outcomes of this project can find applications to quantum sensing and quantum simulation, that would be directly relevant to alkaline-earth-like species that are currently at the core of optical clocks and atom interferometers.

The PULSE project aims at exploring novel temporal regimes in organic lasers. Organic and excitonic thin-film lasers are compact and low-cost sources that are able to emit over the entire visible spectrum and that are compatible with all existing platforms, including flexible or bio-substrates. They can address applications in bio or chemo-sensing, visible light communications or spectroscopy and are anticipated to play a major role in future all-organic or hybrid photonic integrated circuits. They are today however limited to the production of low-intensity nanosecond pulses at low repetition rates under optical pumping. The objective of this project is to head towards new temporal regimes that have never been demonstrated up to now, namely ultrashort pulses and high repetition rate laser action. The strategy consists in implementing recently-discovered materials in the field of organic optoelectronics and nanophotonics into innovative laser architectures. More specifically, two scientific bottlenecks will be targeted. The first one is the “triplet piling-up” problem, which has prevented any solid-state organic laser to operate in the continuous-wave (CW) regime until now. To tackle this issue, we will make good use of recently developed compounds that have shown laser operation in quasi-CW regime, as well as original molecular assemblies with a potential for selective triplet deactivation. The aim will be to obtain laser pulses long enough to ensure stable mode-locking operation. The second bottleneck is the lack of suitable saturable absorbers able to mode-lock solid-state organic lasers: while classical dye saturable absorbers are too slow, fast semiconductor saturable absorbers are not available in the visible part of the spectrum. We propose in this project to work on a new class of saturable absorbers whose properties are very well matched to organic emitters. The timely convergence between the availability of such saturable absorbers and the possibility of long-pulses with organic solid-state lasers make the perspective of demonstrating the first solid-state organic sub-ps laser perfectly realistic in the framework of the PULSE project.

The mid-infrared spectral region (2-20µm) contains the characteristic vibrational transitions of important atmospheric gases (H2O, N2O, CO2, NF3, CH4, O3…). Moreover, in this range there are two atmospheric transparency windows at 3-5µm and 8-13µm and therefore a light beam can propagate over very long distances and investigate the atmosphere remotely. Furthermore, mid-infrared radiation has a lower sensitivity to atmospheric turbulence than at telecoms wavelengths. This is crucial to have accurate, precise and very sensitive measurements for environmental sensing, spectrometry and greenhouse gases (GHG) monitoring. The objective of our proposal is to provide an accurate and compact mid-infrared solar occultation heterodyne radiometry and LIDAR systems. They will employ quantum cascade laser as a source, while the room temperature ultrafast quantum well detectors recently developed at LPENS will be a key advantage in our systems.