Professor Sun works in the general area of many-body physics. His research covers a wide-range of topics including condensed matter physics and ultra-cold atomic gases. The main research efforts in his studies focus on the search for novel states of matter and providing theoretical understanding of their exotic properties. His recent work includes fractional topological states in topological flatbands, interaction induced topological insulators, topological Kondo insulators and holographic elasticity. He has also studied various non-Fermi liquids in strongly correlated fermionic systems, focusing on the quantum liquid crystal phases, and frustrated magnetism.