Continuous symmetry breaking in adaptive quantum dynamics
- URL: http://arxiv.org/abs/2304.13198v1
- Date: Tue, 25 Apr 2023 23:41:35 GMT
- Title: Continuous symmetry breaking in adaptive quantum dynamics
- Authors: Jacob Hauser, Yaodong Li, Sagar Vijay, Matthew P. A. Fisher
- Abstract summary: We introduce an adaptive quantum dynamics with continuous symmetry where unitary operations, measurements, and local unitary feedback are used to drive ordering.
In this setting, we find a pure steady state hosting symmetry-breaking order, which is the ground state of a gapless, local Hamiltonian.
We find that this steady-state order is fragile to perturbations, even those that respect the continuous symmetry.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Adaptive quantum circuits, in which unitary operations, measurements, and
feedback are used to steer quantum many-body systems, provide an exciting
opportunity to generate new dynamical steady states. We introduce an adaptive
quantum dynamics with continuous symmetry where unitary operations,
measurements, and local unitary feedback are used to drive ordering. In this
setting, we find a pure steady state hosting symmetry-breaking order, which is
the ground state of a gapless, local Hamiltonian. We explore the dynamical
properties of the approach to this steady state. We find that this steady-state
order is fragile to perturbations, even those that respect the continuous
symmetry.
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