Showing papers by "Claudio Giannetti published in 2023"
TL;DR: In this article , coherent optical control of the orbital occupation that determines the insulator-to-metal transition in the prototypical Mott insulator was shown to have an electronic coherence time on the order of 5 fs.
Abstract: Managing light-matter interactions on timescales faster than the loss of electronic coherence is key for achieving full quantum control of the final products in solid-solid transformations. In this Letter, we demonstrate coherent optical control of the orbital occupation that determines the insulator-to-metal transition in the prototypical Mott insulator ${\mathrm{V}}_{2}{\mathrm{O}}_{3}$. Selective excitation of a specific interband transition with two phase-locked light pulses manipulates the occupation of the correlated bands in a way that depends on the coherent evolution of the photoinduced superposition of states. A comparison between experimental results and numerical solutions of the optical Bloch equations provides an electronic coherence time on the order of 5 fs. Temperature-dependent experiments suggest that the electronic coherence time is enhanced in the vicinity of the insulator-to-metal transition critical temperature, thus highlighting the role of fluctuations in determining the electronic coherence. These results open different routes to selectively switch the functionalities of quantum materials and coherently control solid-solid electronic transformations.
15 Mar 2023
TL;DR: In this paper , the authors introduce artificial lattices made of lead halide perovskite nanocubes as a new platform to simulate and investigate the physics of correlated quantum materials.
Abstract: The development of Quantum Simulators, artificial platforms where the predictions of many-body theories of correlated quantum materials can be tested in a controllable and tunable way, is one of the main challenges of condensed matter physics. Here we introduce artificial lattices made of lead halide perovskite nanocubes as a new platform to simulate and investigate the physics of correlated quantum materials. The ultrafast optical injection of quantum confined excitons plays the role of doping in real materials. We show that, at large photo-doping, the exciton gas undergoes an excitonic Mott transition, which fully realizes the magnetic-field-driven insulator-to-metal transition described by the Hubbard model. At lower photo-doping, the long-range interactions drive the formation of a collective superradiant state, in which the phases of the excitons generated in each single perovskite nanocube are coherently locked. Our results demonstrate that time-resolved experiments span a parameter region of the Hubbard model in which long-range and phase-coherent orders emerge out of a doped Mott insulating phase. This physics is relevant for a broad class of phenomena, such as superconductivity and charge-density waves in correlated materials whose properties are captured by doped Hubbard models.