Optical Studies of Correlated Magnetic Phases in Twisted MoTe2

Abstract

\par The discovery of integer and fractional quantum Hall effects has motivated the search for their lattice analogs in strongly correlated moir\'e systems. In twisted homobilayer MoTe$_{2}$, fractional Chern insulating phases provide a realization of interaction-driven topological order, where quantized Chern bands emerge from flat moir\'e minibands and are accessible through optical probes such as photoluminescence (PL) and reflective magnetic circular dichroism (RMCD). At small twist angles, MoTe$_{2}$ moir\'e systems enter a strongly correlated regime characterized by narrow minibands and interaction-driven electronic phases. In this regime, stacking configuration (H-stack versus R-stack) and local MX/XM registry play a central role in shaping the moir\'e potential, enabling tunable spin, valley, and layer polarization. \par This thesis investigates twisted MoTe$_{2}$ moir\'e heterostructures using optical spectroscopy to probe correlated magnetic phases across bilayer and trilayer geometries. H-stack devices exhibit strong magnetic-field sensitivity and suppression of trion emission at -2/3 filling, consistent with frustration-driven reconfiguration of spin and layer pseudospin textures, while small-angle R-stack devices show robust inversion symmetry breaking associated with stacking-dependent moir\'e registry and strongly coupled magnetic and layer-polarized states. Extending to trilayers, alternating stacks behave as coupled triangular moir\'e bilayers with enhanced confinement and robust correlated magnetism, whereas helical stacks generate a laterally shifted supermoir\'e potential that reconstructs the electronic landscape and modifies magnetic responses. Together, these results demonstrate that moir\'e geometry, stacking order, and external fields provide a unified route to engineering correlated and magnetic phases in twisted MoTe$_{2}$, accessible through optical probes.