  The rise of programmable quantum devices has motivated the exploration of
circuit models which could realize novel physics. A promising candidate is a
class of hybrid circuits, where entangling unitary dynamics compete with
disentangling measurements. Novel phase transitions between different
entanglement regimes have been identified in their dynamical states, with
universal properties hinting at unexplored critical phenomena. Trapped ion
hardware is a leading contender for the experimental realization of such
physics, which requires not only traditional two-qubit entangling gates, but a
constant rate of local measurements accurately addressed throughout the
circuit. Recent progress in engineering high-precision optical addressing of
individual ions makes preparing a constant rate of measurements throughout a
unitary circuit feasible. Using tensor network simulations, we show that the
resulting class of hybrid circuits, prepared with native gates, exhibits a
volume-law to area-law transition in the entanglement entropy. This displays
universal hallmarks of a measurement-induced phase transition. Our simulations
are able to characterize the critical exponents using circuit sizes with tens
of qubits and thousands of gates. We argue that this transition should be
robust against additional sources of experimental noise expected in modern
trapped ion hardware, and will rather be limited by statistical requirements on
post selection. Our work highlights the powerful role that tensor network
simulations can play in advancing the theoretical and experimental frontiers of
critical phenomena.
