Jaynes Cummings Photonic Superlattices

A classical realization of the Jaynes-Cummings (JC) model, describing the interaction of a two-level atom with a quantized cavity mode, is proposed based on light transport in engineered waveguide superlattices. The optical setting enables to visualize in Fock space dynamical regimes not yet accessible in quantum systems, providing new physical insights into the deep strong coupling regime of the JC model. In particular, bouncing of photon number wave packets in Hilbert space and revivals of populations are explained as generalized Bloch oscillations in an inhomogeneous tight-binding lattice.Comment: 4 pages, 3 figure

Dynamical trapping of light in modulated waveguide lattices

A discrete analogue of the dynamical (Kapitza) trapping effect, known for classical and quantum particles in rapidly oscillating potentials, is proposed for light waves in modulated graded-index waveguide lattices. As in the non-modulated waveguide lattice a graded-index potential can confine light at either normal or Bragg angle incidence, periodic modulation of the potential in the longitudinal direction enables to trap optical beams at both normal and Bragg incidence angles.Comment: to be published in Optics Letter

PT\mathcal{PT} phase control in circular multicore fibers

We consider light dynamics in a circular multicore fiber with balanced gain and loss core distribution, and show that transition from unbroken to broken $\mathcal{PT}$ phases can be conveniently controlled by geometric twist of the fiber. The twist introduces Peierls' phases in the coupling constants and thus acts as an artificial gauge field. As an application, we discuss twist-induced tuning of optical transmission in a six-core fiber with one lossy core.Comment: 6 pages, 4 figures; to appear in Optics Letter

PT-symmetric optical superlattices

The spectral and localization properties of $\mathcal{PT}$-symmetric optical superlattices, either infinitely extended or truncated at one side, are theoretically investigated, and the criteria that ensure a real energy spectrum are derived. The analysis is applied to the case of superlattices describing a complex ($\mathcal{PT}$-symmetric) extension of the Harper Hamiltonian in the rational case.Comment: final version, 7 figures, to appear in J.Phys.

Localization, quantum resonances and ratchet acceleration in a periodically-kicked PT\mathcal{PT}-symmetric quantum rotator

We consider wave transport phenomena in a $\mathcal{PT}$-symmetric extension of the periodically-kicked quantum rotator model and reveal that dynamical localization assists the unbroken $\mathcal{PT}$ phase. In the delocalized (quantum resonance) regime, $\mathcal{PT}$ symmetry is always in the broken phase and ratchet acceleration arises as a signature of unidirectional non-Hermitian transport. An optical implementation of the periodically-kicked $\mathcal{PT}$-symmetric Hamiltonian, based on transverse beam propagation in a passive optical resonator with combined phase and loss gratings, is suggested to visualize acceleration modes in fractional Talbot cavities.Comment: 11 pages, 7 figure

Non-Hermitian gauged topological laser arrays

Stable and phase-locked emission in an extended topological supermode of coupled laser arrays, based on concepts of non-Hermitian and topological photonics, is theoretically suggested. We consider a non-Hermitian Su-Schrieffer-Heeger chain of coupled microring resonators and show that application of a synthetic imaginary gauge field via auxiliary passive microrings leads to all supermodes of the chain, except one, to become edge states. The only extended supermode, that retains some topological protection, can stably oscillate suppressing all other non-topological edge supermodes. Numerical simulations based on a rate equation model of semiconductor laser arrays confirm stable anti-phase laser emission in the extended topological supermode and the role of the synthetic gauge field to enhance laser stability.Comment: 5 figure

Synthetic gauge fields for light beams in optical resonators

A method to realize artificial magnetic fields for light waves trapped in passive optical cavities with anamorphic optical elements is theoretically proposed. In particular, when a homogeneous magnetic field is realized, a highly-degenerate Landau level structure for the frequency spectrum of the transverse resonator modes is obtained, corresponding to a cyclotron motion of the optical cavity field. This can be probed by transient excitation of the passive optical resonator.Comment: 5 pages, 4 figure

Adiabatic quantum state transfer in tight-binding chains using periodic driving fields

A method for high-fidelity coherent adiabatic transport in a zig-zag tight-binding chain, based on application of two external periodic driving fields, is theoretically proposed. The method turns out to be robust against imperfections and disorder of the static lattice Hamiltonian, is tolerant to next-nearest neighborhood interactions, and enables coherent transport in long chains without the need for a local control and timing of the trapping potential.Comment: 6 pages, 4 figures, to appeer in EuroPhysics Letter