We present the experimental demonstration of occurrence exceptional points degeneracy (EPDs) in a single resonator by introducing linear time-periodic variation one its components. This is contrast with requirement two coupled resonators parity time-symmetric systems precise values gain and loss. In proposed scheme, only tuning modulation frequency required, which easily achieved electronic systems. The EPD point system parameters’ space at or more eigenstates coalesce, this leads to unique...

We show that an oscillator array prefers to operate at exceptional point of degeneracy (EPD) occurring in a waveguide periodically loaded with discrete nonlinear gain and radiating elements. The concept the EPD is employed conceptualize synchronization regime, which leads enhanced power efficiency. system maintains steady-state degenerate mode oscillation frequency 3 GHz, even when small-signal values are nonuniform along array. designed using work zero phase shift consecutive unit cells....

A periodically loaded waveguide composed of periodic discrete nonlinear gain and radiating elements supports a stable oscillation regime related to the presence an exceptional point degeneracy (EPD). After reaching saturation, EPD in system establishes frequency. We demonstrate synchronization at frequency, resulting uniform saturated across array power. Unlike conventional one-dimensional cavity resonances, frequency is independent length. Our investigations further show that when...

We propose a scheme for obtaining highly-sensitive oscillators in coupled-resonator system with an exceptional point of degeneracy (EPD) and small instability. The oscillator the is realized by using two coupled resonators almost balanced small-signal gain loss, that saturates due to nonlinear effects active component, resulting oscillation frequency very sensitive perturbation circuit. Two cases are investigated, parallel LC loss either wirelessly mutual inductance or coupled-wired...

We study the rise of exceptional points degeneracy (EPD) in various distinct circuit configurations such as gyrator-based coupled resonators, resonators with PT-symmetry, and a single resonator time-varying component. In particular, we analyze their high sensitivity to changes resistance, capacitance, inductance show resonance frequency perturbations. also investigate stability instability conditions for these configurations; example, effect losses leads instability, it may break symmetry...

We demonstrate that a periodic waveguide comprising of uniform lossless segments together with discrete gain and radiating elements supports exceptional points degeneracy (EPDs). provide analytical expressions for all possible conditions guarantee the occurrence an EPD, i.e., coalescence eigenvalues eigenvectors. show EPDs are not only achieved using symmetric radiation loading, but they also obtained asymmetric loss conditions. illustrate characteristics degenerate electromagnetic modes,...

We introduce a circuit topology based on simple triple-ladder realized with lumped reactive components that provides sixth order degenerate band-edge (6DBE). The 6DBE is special kind of sixth-order exceptional point degeneracy in lossless and gainless periodic ladder. This very flat band edge the phase-frequency dispersion diagram. proposed exhibits unique structured resonance features associated high loaded Q-factor. investigate Floquet-Bloch modes an infinite-length their relation using S...

We demonstrate that a circuit comprising two unstable LC resonators coupled via gyrator supports an exceptional point of degeneracy (EPD) with purely real eigenfrequency. Each the includes either capacitor or inductor negative value, showing imaginary resonance frequency when not to other gyrator. With external perturbation imposed on system, we show analytically response follows square-root dependence perturbation, leading possible sensor applications. Furthermore, effect small losses in...

The first experimental demonstration of an oscillator based on a periodic, resonant microstrip circuit with degenerate band edge (DBE) is presented. DBE fourth-order exceptional degeneracy the eigenmodes in lossless periodic waveguide that visible wavenumber-frequency dispersion diagram, and behaves as frequency selective medium. presence condition associated resonance allow for stable, single-mode oscillation well stability varying load resistance.

We investigate how a single resonator with time-modulated component extracts power from an external ambient source. The collected is largely dependent on the precise modulation signal frequency choice. focus absorbed vibration using mechanical and time of damper can make significant difference in amount harvested power, leading to more than 10 times enhancement compared analogous system without modulation. also find that narrow band pair peak dip spectrum occurs because presence exceptional...

We present a scheme for high-sensitive oscillators based on an exceptional point of degeneracy (EPD) in circuit made two LC resonators coupled by gyrator. The frequency oscillation is very sensitive to perturbations element, like capacitor. show conditions that lead EPD, assuming one the composed inductor and capacitor negative values. EPD occurrence sensitivity linear case are demonstrated showing eigenfrequency bifurcation around described relevant Puiseux (fractional power) series...

An exceptional point of degeneracy (EPD) occurs when two or more eigenvalues and their corresponding eigenvectors coalesce. In the past, EPDs in coupled resonators have been obtained using PT-symmetric circuits. Furthermore, demonstrated a time-varying single LC resonator, via gyrator (K. Rouhi, A. Nikzamir, Figotin, F. Capolino, "Exceptional degenerate system made unstable resonators," Physical Review A, vol. 105, no. 3, 2022) that do not require loss gain components. Here, we present...

We propose a high-sensitive circuit scheme based on an exceptional point of degeneracy (EPD) using two LC resonators coupled with gyrator. EPD is in system's parameter space which or more eigenmodes coalesce both their resonance frequency and eigenvectors into single degenerate eigenmode by varying the system. present conditions to obtain EPDs this typical bifurcation diagram that shows extreme sensitivity such operating at perturbations. The very high induced can be used explore new...

The dispersion of a three-way waveguide is engineered to exhibit exceptional modal characteristics. Two coupled waveguides with parity-time ($\mathcal{P}\mathcal{T}$) symmetry have been previously demonstrated second order points degeneracy (EPDs). In this work, we introduce and investigate particular class EPDs, applicable from radio frequency optical wavelengths, whereby three satisfy glide-time ($\mathcal{G}\mathcal{T}$) third real-valued wave number. $\mathcal{G}\mathcal{T}$ involves...

A scheme for generating oscillations based on an exceptional point of degeneracy (EPD) is proposed in two-coupled resonators made two coupled transmission lines terminated balanced gain and loss, exhibiting a double pole. The EPD the parameter space system at which or more eigenmodes coalesce both their eigenvalues (here, resonance frequencies) eigenvectors. We show that finite-length single line with loss possesses no point, whereas second-order EPDs are enabled (CTLs) loss. demonstrate...

We show the physical realization and experimental demonstration of an exceptional point sixth-order degeneracy in a triple-ladder (or three-way) microwave waveguide realized using three coupled microstrips on grounded dielectric substrate. This three-way supports six Bloch eigenmodes, all coalesce into degenerate single eigenmode at given frequency. The is gainless, this associated with vanishing-group velocity its multiple derivatives. Indeed, $\ensuremath{\omega}\ensuremath{-}k$ dispersion...

Exceptional points of degeneracy (EPD) can enhance the sensitivity circuits by orders magnitude. We show various configurations coupled LC resonators via a gyrator that support EPDs second and third-order. Each resonator includes capacitor inductor with positive or negative value, corresponding EPD frequency could be real imaginary. When perturbation occurs in second-order gyrator-based circuit, we there are two real-valued frequencies shifted from one, following square root law. This is...

We investigate how a single resonator with time-modulated component extracts power from an external ambient source. However, the collected is largely dependent on precise choice of modulation signal frequency. focus absorbed vibration using one degree-of-freedom mechanical where damper has time-varying component. show that time can make significant difference in amount harvested power, leading to more than 10 times enhancement respect analogous system without modulation. also find narrow...

An oscillator array prefers to operate at an exceptional point of degeneracy (EPD) occurring in a waveguide periodically loaded with discrete nonlinear gain and radiating elements. The system maintains steady-state degenerate mode oscillation frequency 3 GHz, even when the small-signal values are nonuniform along array. Contrarily original expectation zero phase shift associated designed EPD using gain, after reaching saturation, time domain signal consecutive unit cells displays $\pi$...

We show how a nonlinear coupled resonator system works in saturated oscillatory regime based on an exceptional point of degeneracy (EPD) to obtain very high sensitivity perturbation. The two resonators are terminated with slightly broken gain and loss PT symmetry. achieve by increasing the (around 1%) than balanced make always unstable. Despite presence nonlinearity this PT-symmetry circuit exhibits Puiseux-like (i.e., square root like) capacitance This high-sensitive double-pole oscillator...

An exceptional point of degeneracy (EPD) is a in parameter space where at least two eigenvalues and eigenvectors system coalesce. We explore the occurrence EPD electronic, electromagnetic mechanical time-varying systems. Remarkably, when using time variation component, EPDs exist single resonator they can be found by just tuning modulation frequency. demonstrate second order linear-time-periodic (LTP) systems offer examples their applications, such as sensing power harvesting.