Fractionalized excitations are key to many unusual many-body states such as quantum spin liquids, disordered phases that cannot be described in terms of any local order parameter. Because these exotic excitations correspond to emergent degrees of freedom, how to probe them and establish their existence is a long-standing challenge. In our recent work, we present a rare mechanism to directly reveal the fractionalized excitations in critical spin liquids using real-space entanglement entropy. Moreover, we demonstrate how to use the entanglement entropy to construct an emergent spinon Fermi surface. Our work opens up a new pathway to establish and characterize exotic excitations in novel quantum phases of matter.

About the speaker: Dr. Wenjun Hu is a postdoctoral research associate at Department of Physics and Astronomy, Rice University. He obtained his Master degree at Renmin University in 2009, and PhD degree at International School for Advanced Studies (SISSA) in Trieste, Italy in 2013. Then he became a postdoc in D. N. Sheng’s group in CSUN, and moved to Rice in 2015. Dr. Hu’s research interest is on studying the frustrated magnetism and other strongly correlated systems in condensed matter physics using various numerical techniques, including variational Monte Carlo, Density Matrix Renormalization Group, etc.