2D materials: from many-body physics to quantum technologies

Because of their dimensionality and unique properties – such as strong light-matter and Coulomb-mediated interactions; valley-contrasting spin physics; extreme sensitivity to the surrounding environment; and gate-tunable carrier concentration- over the past 15 years 2D materials and their heterostructures have flourished as a leading condensed-matter platform to study a plethora of exotic quantum many-body effects, from complex excitonic species to a zoo of strongly correlated states [1].

Building on these results, 2D materials have been taking centre stage in the ever-increasing effort to develop viable material platforms for quantum technologies . Their combination of scalability, good optical properties, and long spin coherence time predicted, offers an exciting route to overcome bottlenecks that have been hampering traditional solid-state, optically active quantum platforms for the past 30 years [2].

In my talk, I will introduce some of the foundational physical aspects of layered materials, including stable excitonic complexes up to twenty particles large [3,4], the emergent role of dynamic dielectric screening effects underpinning Coulomb interactions [5], as well as correlated states [6,7] in twisted transition metal dichalcogenides (TMD) bilayers.

I will then address the quest to expand 2D materials to quantum technology, reviewing progress towards real-life on-chip quantum photonic applications, from deterministic positioning of large-scale arrays of single-photon sources [8], to electrical generation of single-photons [9], injection of single charges to form spin-photon interfaces, coupling to photonic structures, and, most recently, substrate-independent single-photon detection in superconducting nanowire devices [10].

Finally, I will pinpoint outstanding challenges and discuss how recent scientific and technological breakthroughs, including sub-10 nm nanofabrication capabilities and heterointegration with oxide electronics, unlock thrilling opportunities ahead, from novel polaritonic effects to entanglement-driven dynamics in (synthetic) quantum matter [11].