SAMOP 2021 – wissenschaftliches Programm
SYAD 1.3: Hauptvortrag
Dienstag, 21. September 2021, 11:45–12:15, Audimax
Supersolid Arrays of Dipolar Quantum Droplets — •Fabian Böttcher — 5. Physikalisches Institut, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart
The observation of a supersolid -- a paradoxical state of matter characterized by the coexistence of crystalline order and superfluidity -- has been a challenge since its first prediction in the 1950s. Initial experimental and theoretical investigations focused mainly on solid helium where supersolidity still remains elusive. In recent years, ultracold atomic gases have provided a new experimental approach and have allowed the observation of supersolidity in dipolar quantum gases.
Already classical magnetic ferrofluids can show many interesting phenomena, such as self-organization and spontaneous symmetry breaking. Ultracold dipolar quantum gases bring these phenomena into the quantum world. In dipolar quantum gasses, the constituent particles can interact via the short-range contact interaction and the long-range and anisotropic dipole-dipole interaction. The precise interplay of these two interactions in combination with the intrinsic quantum fluctuations leads to the emergence of liquid-like quantum droplets. Confining these quantum droplets leads to their fragmentation into arrays of multiple droplets, realizing a purely self-organized supersolid state of matter. Experimentally, we prove the supersolid nature of these droplet arrays by observing their characteristic periodic density modulation, their global phase coherence and the superfluid dynamics of low-energy excitation modes.