Photonic Berry curvature in double liquid crystal microcavities with broken inversion symmetry

We investigate a photonic device consisting of two coupled optical cavities possessing Rashba-Dresselhaus spin-orbit coupling, TE-TM splitting, and linear polarisation splitting that opens a tuneable energy gap at the diabolic points of the photon dispersion; giving rise to an actively addressable local Berry curvature. The proposed architecture stems from recent advancements in the design of artificial photonic gauge fields in liquid crystal cavities [K. Rechci\'{n}ska et al., Science 366, 727 (2019)]. Our study opens new perspectives for topological photonics, room-temperature spinoptronics, and studies on the quantum geometrical structure of photonic bands in extreme settings

Non-Hermitian skin effect induced by Rashba-Dresselhaus spin-orbit coupling

International audience1D chains with non-reciprocal tunneling realizing the non-Hermitian skin effect (NHSE) have attracted considerable interest in the last years whereas their experimental realization in real space remains limited to a few examples. In this work, we propose a new generic way of implementing non-reciprocity based on a combination of the Rashba-Dresshlauss spin-orbit coupling, existing for electrons, cold atoms, and photons, and a lifetime imbalance between two spin components. We show that one can realize the Hatano-Nelson model, the non-Hermitian Su-Schrieffer-Heeger model, and even observe the NHSE in a 1D potential well without the need for a lattice. We further demonstrate the practical feasibility of this proposal by considering the specific example of a photonic liquid crystal microcavity. This platform allows one to switch on and off the NHSE by applying an external voltage to the microcavity

Photonic Berry curvature in double liquid crystal microcavities with broken inversion symmetry

We investigate a photonic device consisting of two coupled optical cavities possessing Rashba-Dresselhaus spin-orbit coupling, TE-TM splitting, and linear polarization splitting that opens a tunable energy gap at the diabolic points of the photon dispersion; giving rise to an actively addressable local Berry curvature. The proposed architecture stems from recent advancements in the design of artificial photonic gauge fields in liquid crystal cavities [K. Rechcińska, Science 366, 727 (2019)SCIEAS0036-807510.1126/science.aay4182]. Our study opens perspectives for topological photonics, room-temperature spinoptronics, and studies on the quantum geometrical structure of photonic bands in extreme settings.</p

Control of dimer chain topology by Rashba-Dresselhaus spin-orbit coupling

We study theoretically a dimer chain in the presence of Rashba-Dresselhaus spin-orbit coupling (RDSOC) with equal strength. We show that the RDSOC can be described as a synthetic gauge field that controls not only the magnitude but also the sign of tunneling coefficients between sites. This allows to emulate not only a Su-Schrieffer-Heeger chain which is commonly implemented in various platforms, but also, all energy spectra of the transverse field Ising model with both ferromagnetic and antiferromagnetic coupling. We simulate a realistic implementation of these effective Hamiltonians based on liquid crystal microcavities. In that case, the RDSOC can be switched on and off by an applied voltage, which controls the band topology, the existence and characteristics of topological edge states, or the nature of the ground state. This setting is promising for topological photonics applications and from a quantum simulation perspective

Data for Photonic Berry curvature in double liquid crystal microcavities with broken inversion symmetry

Data from modelling used to create the figures in the paper Kokhanchik, P., Sigurdsson, H., Pi&#x119;tka, B., Szczytko, J., and Lagoudakis P. G. (2021). Photonic Berry curvature in double liquid crystal microcavities with broken inversion symmetry. Physical Review B.</span

Control of dimer chain topology by Rashba-Dresselhaus spin-orbit coupling

We study theoretically a dimer chain in the presence of Rashba-Dresselhaus spin-orbit coupling (RDSOC) with equal strength. We show that the RDSOC can be described as a synthetic gauge field that controls not only the magnitude but also the sign of tunneling coefficients between sites. This allows to emulate not only a Su-Schrieffer-Heeger chain which is commonly implemented in various platforms, but also, all energy spectra of the transverse field Ising model with both ferromagnetic and antiferromagnetic coupling. We simulate a realistic implementation of these effective Hamiltonians based on liquid crystal microcavities. In that case, the RDSOC can be switched on and off by an applied voltage, which controls the band topology, the existence and characteristics of topological edge states, or the nature of the ground state. This setting is promising for topological photonics applications and from a quantum simulation perspective

Modulated Rashba-Dresselhaus Spin-Orbit Coupling for Topology Control and Analog Simulations

International audienceWe show theoretically that Rashba-Dresselhaus spin-orbit coupling (RDSOC) in lattices acts as a synthetic gauge field. This allows us to control both the phase and the magnitude of tunneling coefficients between sites, which is the key ingredient to implement topological Hamitonians and spin lattices useful for simulation perpectives. We use liquid crystal based microcavities in which RDSOC can be switched on and off as a model platform. We propose a realistic scheme for implementation of a Su-Schrieffer-Heeger chain in which the edge states existence can be tuned, and a Harper-Hofstadter model with a tunable contrasted flux for each (pseudo)spin component. We further show that a transverse-field Ising model and classical XY Hamiltonian with tunable parameters can be implemented, opening up prospects for analog physics, simulations, and optimization