Entanglement entropy as a portal to the physics of quantum spin liquids

Quantum spin liquids (QSLs) are phases of interacting spins that do not order even at the absolute zero temperature, making it impossible to characterize them by a local order parameter. In this paper, we review the unique view provided by the quantum entanglement on QSLs. We illustrate the crucial role of topological entanglement entropy in diagnosing the non-local order in QSLs, using specific examples such as the chiral spin liquid. We also demonstrate the detection of anyonic quasi-particles and their braiding statistics using quantum entanglement. In the context of gapless QSLs, we discuss the detection of emergent fermionic spinons in a bosonic wavefunction, by studying the size dependence of entanglement entropy.