A critical system coupled to ancillas that are subsequently measured.
Measurements can do more than reveal a quantum state: they can change its correlations and entanglement. I study how measurement protocols modify critical many-body systems, with a particular focus on systems described by conformal field theories (CFTs). I use field-theory methods to understand the resulting universal behaviour and work with experimental collaborators to explore it in quantum simulators.
Measurement-altered Ising quantum criticality. S. Murciano, P. Sala, Y. Liu, R. S. K. Mong, J. Alicea. Phys. Rev. X 13, 041042 (2023).
Observation of conformal field theory spectra in a quantum simulator. X. Sun, Y. Le, S. Naus, R. B.-S. Tsai, L. R. B. Picard, S. Murciano, M. Knap, J. Alicea, M. Endres. Nature 657, 98–106 (2026).
I study the interplay between entanglement and symmetries in quantum many-body systems, including both symmetry conservation and symmetry breaking. My work explores how entanglement is distributed across symmetry sectors and how it can reveal symmetry breaking. These questions connect to quantum resource theories, including the characterisation of non-Gaussianity, and have applications in quantum technologies. For instance, our recent work shows how the symmetries of a many-body state can be used to improve measurement precision in quantum sensing.
Symmetry-resolved entanglement entropy in Wess–Zumino–Witten models. P. Calabrese, J. Dubail, S. Murciano. JHEP 10, 067 (2021).
Non-Gaussianity of random quantum states. F. Ares, S. Murciano, P. Calabrese. arXiv:2605.18986 (2026).
Quantum sensing with critical systems: impact of symmetry, imperfections, and decoherence. Y. Chen, S. Murciano, P. Sala, J. Alicea. arXiv:2601.04364 (2026).
Symmetry organises the reduced density matrix into distinct sectors.
The Mpemba effect: a state initially farther from equilibrium can relax faster.
I study quantum dynamics through the evolution of entanglement, symmetries and operators. I have used the entanglement asymmetry to study symmetry breaking and anomalous symmetry restoration, including a quantum version of the Mpemba effect in closed systems, where a state that breaks the symmetry more at initial time can restore it faster. I also investigate out-of-equilibrium quantities such as negativity and operator entanglement, using the latter to characterise the complexity of evolving operators and density matrices.
Entanglement asymmetry as a probe of symmetry breaking. F. Ares, S. Murciano, P. Calabrese. Nature Communications 14, 2036 (2023).
Entanglement Barrier and its Symmetry Resolution: Theory and Experimental Observation. A. Rath, V. Vitale, S. Murciano, M. Votto, J. Dubail, R. Kueng, C. Branciard, P. Calabrese, B. Vermersch. PRX Quantum 4, 010318 (2023).