XBEC · Exploring Bose-Einstein Condensation of Excitons and Related Quantum Phases

This research proposal aims at harnessing collective quantum phenomena in semiconductors in order to deterministically engineer quantum states of matter. For this purpose, the techniques successfully pioneered in atomic physics will be transposed to the solid-state. As envisioned by R. Feynman, this approach offers the formidable opportunity to emulate emblematic collective quantum phenomena and to radically deepen our understanding of quantum physics. At the same time, it opens a route to develop a novel generation of devices that have direct applications in the context of quantum information science. The ambitious goal of the project will be pursued by employing the unique physical properties of spatially indirect excitons confined in bilayer semiconductor heterostructures. Indirect excitons are boson-like quasi-particles which exhibit a very long lifetime and a well defined electric dipole. These will allow us to engineer a complete toolbox for the quantum control of the exciton wave-function. To this aim, we conceived an innovative approach where an advanced technology for trapping indirect excitons is enriched by quantum optical techniques. Thus, a scheme is elaborated to unambiguously demonstrate Bose-Einstein condensation of semiconductor excitons. Precisely, this research proposal introduces two main objectives: i) the realization of microscopic trapping potentials where the effective temperature of exciton gases is dynamically controlled. ii) the development of artificial lattices to engineer exciton crystals and develop a solid-state quantum simulator. Reaching these objectives would lead to an unprecedented level of control over ultra-cold exciton gases. This would open new horizons in order to study the foundations of quantum many-body physics and to develop novel quantum technologies.