Multipartite Entanglement in the Measurement-Induced Phase Transition of the Quantum Ising Chain

Understand

External monitoring of quantum many-body systems can give rise to a measurement-induced phase transition characterized by a change in behavior of the entanglement entropy from an area law to an unbounded growth.

• In this Letter, we show that this transition extends beyond bipartite correlations to multipartite entanglement.
• Using the quantum Fisher information, we investigate the entanglement dynamics of a continuously monitored quantum Ising chain.
• Multipartite entanglement exhibits the same phase boundaries observed for the entropy in the post-selected no-click trajectory.