内容摘要：Exciton condensation and exciton insulators are at the frontier areas in current quantum materials research, potentially leading to the emergence of new phenomena and physics. Traditional studies utilize laser excitation to generate electron-hole pairs in semiconductors, which, due to Coulomb interaction, form exciton pairs with zero momentum (k=0) and form a transient exciton condensate at low temperatures, evidenced by interference patterns in the spatially distributed emission spectrum. In bilayer fractional quantum Hall (FQH) systems, interlayer many-body electron interactions under a magnetic field can form a QH exciton condensate and exhibit a superfluid state of bilayer counterflow. In recent experiments, we found that in bilayer electron-hole systems, within a wide range of unequal electron-hole concentrations, due to the non-zero momentum of the formed excitons (k ≠ 0) and the frustration effect of exciton pairing, the ground state of the system under many-body interaction may no longer be an exciton condensate, but a new state with extremely large degeneracy, called Excitonic Topological Order. Because this type of emergent effect caused by condensation breaking is widespread, it is possible to use different experimental knobs to guide the emergence of new states and their fractional excitations in this system.