| Abstract: | The measurement-induced phase transition (MPT) is a class of dynamical phase transitions occurring in quantum states undergoing non-unitary evolution. Typically, the non-unitary operator is constructed out of entangling unitary gates interspersed with measurements, leading to a competition between the entangling effect of the gates and the disentalging effect of the measurements. In the semiclassical limit this transition is mapped to a simple percolation problem, where measurements eliminate network edges. Interestingly however, in the general case the classical percolation threshold of the circuit structure and the MPT are distinct, much like the separation between mean-field and fluctuation-driven transitions. This raises a fascinating and open question regarding the universal properties of the MPT in the general case. One approach to addressing this question has been the use of Clifford circuits, where the MPT and naive percolation threshold are also distinct, whilst large scale numerical simulation is accessible through the Gottesman-Knill theorem. In this talk I will use ZX-calculus to demonstrate that the MPT in Clifford circuits corresponds to a classical percolation transition. |