Exploring Novel Quantum Phases in Ultracold Magnetic Gases: Dipolar Supersolids and Ferromagnetic Phases in Spinor Condensates

Novel magnetic phases arising from quantum phase transitions are at the frontier in ultracold quantum gases experiments. In this thesis, I focus on two different phases: the dipolar supersolid found in quantum gases with dipolar interactions, and the easy-plane ferromagnetic phase realized in a spin-1 spinor condensate. Being a novel quantum phase of matter, the dipolar supersolid still needs to be explored in its complexity, but some of its defining properties have been already assessed in experiments. The two main results I discuss in the thesis are the study of the quantum phase transition leading to the formation of dipolar supersolids, and the first measurement of their reduced superfluid response. In the context of spinor condensates, I discuss my contribution to a preliminary investigation of novel topological excitations resulting from a quench across a phase transition connecting the polar phase to the easy-plane ferromagnetic phase in a spin-1 system.