Non-Hermitian electronics multipods of electromagnetically induced transparency (EIT) and absorption (EIA)

Abstract

We study a non-Hermitian electronic dimers system based on an imaginary resistor (Z) in a (N+2) level atomic multi-pod configuration. Non-Hermitian systems depend on a gain/loss parameter and are specifically marked by a degeneracy exhibited at an exceptional point (EP) separating different phases of complex modes dynamics. Interestingly, the structural characterization and the dispersive properties reveal a broad range of strong coupling where the interplay between the control and the probe field induce a simultaneous EIT, EIA and ATS. Here, by identifying the underlying physical mechanisms, we show that multiple windows of transparency can be strongly enhanced by the incorporation of several dimers in the multipod network. On the other hand, if the pumping field is resonant in the weak regime, multiple EIT and EIA windows result in the number of dimers. Remarkably, the proposed system embedded a multiple coupling mechanism whose modulation induces a couplingless point whereby the energy cross. At this point EIT and related phenomena vanish.

Hall conductance of a non-Hermitian Weyl semimetal

“…Interestingly, recent studies show that the particular class of unitary (pseudo-Hermiticity) and combination of unitary and anti-unitary (parity-time) symmetry leads to striking consequences in transport properties in various platforms ranging from waveguide systems to electrical set up. Delving into the electrical realm, the authors in [84] explore a NH electronic dimer system based on an imaginary resistor (Z) in a (N + 2) level atomic multipod configuration. NH systems, characterized by a gain/loss parameter governed by particular symmetries, exhibit a degeneracy at an EP that separates different phases of complex mode dynamics.…”

A Mid-Infrared Multifunctional Optical Device Based on Fiber Integrated Metasurfaces

“…However, trapped modes often require other ways of excitation, such as breaking the structural symmetry or using the oblique incidence of electromagnetic waves. We can first use the Lorentz resonance model to analyze the interactions between the modes from an academic perspective [35,36]:…”

PT-symmetric electronic dimer without gain material

“…Its main characteristic is the ability to generate frequency independent phase shift, unlike inductor/capacitor reactive elements, which can only do this task when they are associated with a nonzero frequency [20]. Indeed, it was proven that it can validly replace an inductance L, so that the first order resonance oscillator ZRC can be proposed to substitute the conventional second order resonance oscillator LRC [15,[21][22][23]. The use of the imaginary resistance allows efficient manipulation of higher and smaller positive/negative frequencies.…”