# Floquet conformal field theories with generally deformed Hamiltonians

### Submission summary

 As Contributors: Ruihua Fan Preprint link: scipost_202102_00012v1 Date accepted: 2021-02-17 Date submitted: 2021-02-09 04:07 Submitted by: Fan, Ruihua Submitted to: SciPost Physics Academic field: Physics Specialties: Dynamical Systems Condensed Matter Physics - Theory Quantum Physics Approach: Theoretical

### Abstract

In this work, we study non-equilibrium dynamics in Floquet conformal field theories (CFTs) in 1+1D, in which the driving Hamiltonian involves the energy-momentum density spatially modulated by an arbitrary smooth function. This generalizes earlier work which was restricted to the sine-square deformed type of Floquet Hamiltonians, operating within a $\mathfrak{sl}_2$ sub-algebra. Here we show remarkably that the problem remains soluble in this generalized case which involves the full Virasoro algebra, based on a geometrical approach. It is found that the phase diagram is determined by the stroboscopic trajectories of operator evolution. The presence/absence of spatial fixed points in the operator evolution indicates that the driven CFT is in a heating/non-heating phase, in which the entanglement entropy grows/oscillates in time. Additionally, the heating regime is further subdivided into a multitude of phases, with different entanglement patterns and spatial distribution of energy-momentum density, which are characterized by the number of spatial fixed points. Phase transitions between these different heating phases can be achieved simply by changing the duration of application of the driving Hamiltonian. We demonstrate the general features with concrete CFT examples and compare the results to lattice calculations and find remarkable agreement.

Published as SciPost Phys. 10, 049 (2021)

### Submission & Refereeing History

Resubmission scipost_202102_00012v1 on 9 February 2021
Submission 2011.09491v2 on 10 December 2020

## Reports on this Submission

### Report

The authors have implemented the changes requested and I think the paper is ready for publication in Scipost.

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