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Description
A topological dynamical phase transition is induced between two planar superconducting phases. Using the Lindblad equation to account for the interactions of Bogoliubov quasiparticles among themselves and with the fluctuations of the superconducting order parameter, the relaxation dynamics of the order parameter is analyzed [1]. To characterize the phase transition, the fidelity and the spin-Hall conductance of the open system are computed [2]. The approach provides crucial information for experimental implementations, such as the dependence of the critical time on the system-bath coupling. The modern theory of electric polarization is generalized to the case of one-dimensional non-Hermitian systems with a line-gapped spectrum [3]. Moreover, the nonperturbative effects induced by the environment are investigated in the prototype Su-Schrieffer-Heeger chain coupled to local harmonic oscillator baths through either intracell or intercell transfer integrals [4]. Despite the common view, this type of coupling, if suitably engineered, can even induce a transition to topological phases. By using a world-line quantum Monte Carlo technique, the phase diagram of the model is determined proving that the bimodality of the probability distribution of the polarization signals the emergence of the topological phase. Finally, a qualitative description can be obtained by using an approach based on the cluster perturbation theory providing, in particular, a non-Hermitian Hamiltonian for the fermionic subsystem.
References
[1] A. Nava, C. A. Perroni, R. Egger, L. Lepori, D. Giuliano, “Lindblad master equation approach to the dissipative quench dynamics of planar superconductors”, Phys. Rev. B 108, 245129 (2023).
[2] A. Nava, C. A. Perroni, R. Egger, L. Lepori, D. Giuliano, “Dissipation-driven dynamical topological phase transitions in two-dimensional superconductors”, Phys. Rev. B 109, L041107 (2024).
[3] J. Hu, C. A. Perroni, G. De Filippis, S. Zhuang, L. Marrucci, F. Cardano “Electric polarization and its quantization in one-dimensional non-Hermitian chains, Phys. Rev. B 107, L121101 (2023).
[4] F. Pavan, A. de Candia, G. Di Bello, V. Cataudella, N. Nagaosa, C. A. Perroni, G. De Filippis, “Witnessing environment induced topological phase transitions via quantum Monte Carlo and cluster perturbation theory studies”, Phys. Rev. B 109, 115147 (2024).
