Aleksandra Maluckov

• Doctor of Philosophy
• Professor at Vinča Institute of Nuclear Sciences

Modulational instability in topological photonic lattices enables the selective population of energy bands and generation of steady-state wavefields with well-defined topological invariants. Here we study numerically the process of wave thermalization arising from modulational instability in topological bands. We apply a grand canonical approach to...

Highlights Novel interconnects based on linearly coupled waveguide arrays. High-fidelity information transfer without the crosstalk-induced loss. An order of magnitude higher channel density than in conventional interconnects. Inverse design applicable to the long-haul, short-range and on-chip interconnects. Compatible with the standard modulation...

In the present work we revisit the Salerno model as a prototypical system that interpolates between a well-known integrable system (the Ablowitz-Ladik lattice) and an experimentally tractable, nonintegrable one (the discrete nonlinear Schrödinger model). The question we ask is, for “generic” initial data, how close are the integrable to the noninte...

In the present work we revisit the Salerno model as a prototypical system that interpolates between a well-known integrable system (the Ablowitz-Ladik lattice) and an experimentally tractable non-integrable one (the discrete nonlinear Schr\"odinger model). The question we ask is: for "generic" initial data, how close are the integrable to the non-i...

Multiarm interferometers can enhance measurement precision and provide multiparameter capability to the measurement. Their realisation requires multiport beam splitters, which has been a long-standing challenge in free-space and integrated optics. Here, we propose a new type of multiport interferometers suitable for implementation on optical chips....

Multiarm interferometers can enhance measurement precision and provide multiparameter capability to the measurement. Their realisation requires multiport beam splitters, which has been a long-standing challenge in free-space and integrated optics. Here, we propose a new type of multiport interferometers suitable for implementation on optical chips....

We study how the nonlinear propagation dynamics of bulk states may be used to distinguish topological phases of slowly driven Floquet lattices. First, we show how instabilities of nonlinear Bloch waves may be used to populate Floquet bands and measure their Chern number via the emergence of nontrivial polarization textures in a similar manner to st...

Tuning the values of artificial flux in the two-dimensional octagonal-diamond lattice drives topological phase transitions, including between singular and non-singular flatbands. We study the dynamical properties of nonlinear compact localized modes that can be continued from linear flatband modes. We show how the stability of the compact localized...

Two-dimensional dice lattice can be dressed by artificial flux to host the Aharonov-Bohm (AB) caging effect resulting in the occurrence of a fully flatband spectrum. Here, we focus on the dynamics of flatband compact localized eigenmodes shared by a few unit cells in two snowflake configurations. We numerically show the possibility of dynamically s...

Tuning the values of artificial flux in the two-dimensional octagonal-diamond lattice drives topological phase transitions, including between singular and non-singular flatbands. We study the dynamical properties of nonlinear compact localized modes that can be continued from linear flatband modes. We show how the stability of the compact localized...

We study how the nonlinear propagation dynamics of bulk states may be used to distinguish topological phases of slowly-driven Floquet lattices. First, we show how instabilities of nonlinear Bloch waves may be used to populate Floquet bands and measure their Chern number via the emergence of nontrivial polarization textures in a similar manner to st...

We challenge the current thinking and approach to the design of photonic integrated circuits (PICs) for applications in communications, quantum information and sensing. The standard PICs are based on directional couplers, that provide a wide range of functionalities but do not fully respond to the major technological challenges: massive parallelisa...

Active multi‐core fibers represent a powerful platform for coding information via power, phase, frequency, and topological charge, as presented by Petra P. Beličev, Sergei Turitsyn, and co‐workers in article number 2100108. Depending on the gain distribution between the periphery and central core, the system supports multiple functions in applicati...

Topological properties can make light field remarkably robust to various external perturbations. The ability to control and change on demand topological characteristics of light paves the way to new interesting physical phenomena and applications. Here, numerical modelling design of the device based on active multi‐core fiber that can change topolo...

The Salerno model constitutes an intriguing interpolation between the integrable Ablowitz-Ladik (AL) model and the more standard (nonintegrable) discrete nonlinear Schrödinger (DNLS) one. The competition of local on-site nonlinearity and nonlinear dispersion governs the thermalization of this model. Here, we investigate the statistical mechanics of...

We study the properties of nonlinear Bloch waves in a diamond chain waveguide lattice in the presence of a synthetic magnetic flux. In the linear limit, the lattice exhibits a completely flat (wavevector k-independent) band structure, resulting in perfect wave localization, known as Aharonov–Bohm caging. We find that in the presence of nonlinearity...

We analyze the modulational instability of nonlinear Bloch waves in topological photonic lattices. In the initial phase of the instability development captured by the linear stability analysis, long wavelength instabilities and bifurcations of the nonlinear Bloch waves are sensitive to topological band inversions. At longer timescales, nonlinear wa...

The Salerno model constitutes an intriguing interpolation between the integrable Ablowitz-Ladik (AL) model and the more standard (non-integrable) discrete nonlinear Schr{\"o}dinger (DNLS) one. The competition of local on-site nonlinearity and nonlinear dispersion governs the thermalization of this model. Here, we investigate the statistical mechani...

We investigate analytically and numerically the existence and dynamical stability of different localized modes in a two-dimensional photonic lattice comprising a square plaquette inscribed in the dodecagon lattices. The eigenvalue spectrum of the underlying linear lattice is characterized by a net formed of one flat band and four dispersive bands....

We consider a two-dimensional octagonal-diamond network with a fine-tuned diagonal coupling inside the diamond-shaped unit cell. Its linear spectrum exhibits coexistence of two dispersive bands (DBs) and two flat bands (FBs), touching one of the DBs embedded between them. Analogous to the kagome lattice, one of the FBs will constitute the ground st...

We analyze the modulational instability of nonlinear Bloch waves in topological photonic lattices. In the initial phase of the instability development captured by the linear stability analysis, long wavelength instabilities and bifurcations of the nonlinear Bloch waves are sensitive to topological band inversions. At longer timescales, nonlinear wa...

The linear diamond chain with fine-tuned effective magnetic flux has a completely flat energy spectrum and compactly localized eigenmodes, forming an Aharonov-Bohm cage. We study numerically how this localization is affected by different types of disorder (static and time-evolving) relevant to recent realizations of Aharonov-Bohm cages in periodica...

In this paper, we establish a new scheme for identification and classification of high intensity events generated by the propagation of light through a photorefractive SBN crystal. Among these events, which are the inevitable consequence of the development of modulation instability, are speckling and soliton-like patterns. The usual classifiers dev...

In this paper, we establish a new scheme for identification and classification of high intensity events generated by the propagation of light through a photorefractive SBN crystal. Among these events, which are the inevitable consequence of the development of modulation instability, are speckling and soliton-like patterns. The usual classifiers, de...

Quantum droplets are ultradilute liquid states that emerge from the competitive interplay of two Hamiltonian terms, the mean-field energy and beyond-mean-field correction, in a weakly interacting binary Bose gas. We relate the formation of droplets in symmetric and asymmetric two-component one-dimensional boson systems to the modulational instabili...

A quantum droplet is a liquid state which emerges from the competitive interaction of two energy scales, the mean-field energy and the beyond-mean-field correction to the energy of a weakly interacting Bose gas. Here, we analyze both the stability and generating mechanisms of such droplets in a one-dimensional model of weakly interacting binary Bos...

The linear diamond chain with fine-tuned effective magnetic flux has a completely flat energy spectrum and compactly-localized eigenmodes, forming an Aharonov-Bohm cage. We study numerically how this localization is affected by different types of disorder (static and time-evolving) relevant to recent realizations of Aharonov-Bohm cages in periodica...

We examine the supercontinuum (SC) dependence on the chirp of the input laser beam and effects of input pulse noise. Simultaneously, we investigate the relation between the SC generation and creation of localized high intensity events. We show that despite their low probability, these events inevitably appear in the SC in our setup. Their devastati...

Atrial fibrillation (AF) and atrial flutter (AFL) represent atrial arrhythmias closely related to increasing risk for embolic stroke, and therefore being in the focus of cardiologists. While the reported methods for AF detection exhibit high performances, little attention has been given to distinguishing these two arrhythmias. In this study, we pro...

We report on the excitation of large-amplitude waves, with a probability of around 1% of total peaks, on a photorefractive SBN crystal by using a simple experimental setup at room temperature. We excite the system using a narrow Gaussian beam and observe different dynamical regimes tailored by the value and time rate of an applied voltage. We ident...

We report on the excitation of large-amplitude waves, with a probability of around 1% of total peaks, on a photorefractive SBN crystal by using a simple experimental setup at room temperature. We excite the system using a narrow Gaussian beam and observe different dynamical regimes tailored by the value and time rate of an applied voltage. We ident...

We study nonlinear dynamics of the DNA molecule relying on a helicoidal Peyrard–Bishop model. We look for traveling wave solutions and show that a continuum approximation brings about kink solitons moving along the chain. This statement is supported by the numerical solution of a relevant dynamical equation of motion. Finally, we argue that an exis...

We study the interaction of the medium composed of three-level atoms in A configuration interacting with two laser fields: weak probe field and strong control field. The probe field enters the medium under a certain angle, and it is initially in the form of the spatial soliton, while the control field is periodically modulated. The system of optica...

We have obtained the matter wave soliton solution for the driven nonautonomous GP equation with quadratic–cubic nonlinearities. We have revealed their interesting dynamical features for the experimentally realizable form of nonlinear interactions. Additionally, we have described that by suitably choosing some system parameters, we can control their...

We study the influence of mean-field cubic nonlinearity on Aharonov-Bohm caging in a diamond lattice with synthetic magnetic flux. For sufficiently weak nonlinearities, the Aharonov-Bohm caging persists as periodic nonlinear breathing dynamics. Above a critical nonlinearity, symmetry breaking induces a sharp transition in the dynamics and enables s...

Objective: Algorithms to predict shock outcome based on ventricular fibrillation (VF) waveform features are potentially useful tool to optimize defibrillation strategy (immediate defibrillation versus cardiopulmonary resuscitation). Researchers have investigated numerous predictive features and classification methods using single VF feature and/or...

We study the influence of mean field cubic nonlinearity on Aharonov-Bohm caging in a diamond lattice with synthetic magnetic flux. For sufficiently weak nonlinearities the Aharonov-Bohm caging persists as periodic nonlinear breathing dynamics. Above a critical nonlinearity, symmetry breaking induces a sharp transition in the dynamics and enables st...

In this paper, we investigate broadband supercontinuum generation in photonic crystal fibers using cosh-Gaussian optical pulses, which provide flatter spectrum than standard Gaussian pulses. This fact can be crucial for telecommunication systems applications. The intensive numerical study of three main telecommunication windows pointed out the most...

We present a statistical analysis based on the height and return-time probabilities of high-amplitude wave events in both focusing and defocusing Manakov systems. We find that analytical rational or semirational solutions, associated with extreme, rogue wave (RW) structures, are the leading high-amplitude events in this system. We define the thresh...

We present a statistical analysis based on the height and return time probabilities of high amplitude wave events in both focusing and defocusing Manakov systems. We find that analytical rational/semirational solutions, associated with extreme, rogue wave (RW) structures, are the leading high amplitude events in this system. We define the threshold...

Linear wave equations on flat band networks host compact localized eigenstates (CLS). Nonlinear wave equations on translationally invariant flat band networks can host compact discrete breathers - time periodic and spatially compact localized solutions. Such solutions can appear as one-parameter families of continued linear compact eigenstates, or...

Linear wave equations on flat band networks host compact localized eigenstates (CLS). Nonlinear wave equations on translationally invariant flat band networks can host compact discrete breathers - time periodic and spatially compact localized solutions. Such solutions can appear as one-parameter families of continued linear compact eigenstates, or...

We report on the excitation of large-amplitude waves, with very low probability, in photorefractive SBN crystals. We excite the system with a narrow gaussian beam and observe different dynamical regimes tailored by the crystal nonlinearity.

Compact localized modes of ring type exist in many two-dimensional lattices with a flat linear band, such as the Lieb lattice. The uniform Lieb lattice is gapless, but gaps surrounding the flat band can be induced by various types of bond alternations (dimerizations) without destroying the compact linear eigenmodes. Here, we investigate the conditi...

We address the stability and dynamics of eigenmodes in linearly-shaped strings (dimers, trimers, tetramers, and pentamers) built of droplets of a binary Bose-Einstein condensate (BEC). The binary BEC is composed of atoms in two pseudo-spin states with attractive interactions, dressed by properly arranged laser fields, which induce the (pseudo-) spi...

We address the stability and dynamics of eigenmodes in linearly-shaped strings (dimers, trimers, tetramers, and pentamers) built of droplets of a binary Bose-Einstein condensate (BEC). The binary BEC is composed of atoms in two pseudo-spin states with attractive interactions, dressed by properly arranged laser fields, which induce the (pseudo-) spi...

By introducing evolving disorder in the binary kagome ribbons, we study the establishment of diffusive spreading of flat band states characterized by diffractionless propagation in regular periodic ribbons. Our numerical analysis relies on controlling strength and rate of change of disorder during light propagation while tailoring binarism of the k...

Extreme events (EEs) in nonlinear and/or disordered one-dimensional photonic lattice systems described by the Salerno model with on-site disorder are studied. The goal is to explain particular properties of these phenomena, essentially related to localization of light in the presence of nonlinear and/or nonlocal couplings in the considered systems....

Time statistics of extreme events (EEs) in one-dimensional discrete Salerno lattices is investigated numerically. We show that the dependence of the mean return time of EEs on the amplitude threshold can be used as a criterion to differentiate between various dynamical regimes of the extreme events. Also, we found that dispersion of points on the t...

We report the coexistence and properties of stable compact localized states (CLSs) and discrete solitons (DSs) for nonlinear spinor waves on a flatband network with spin-orbit coupling (SOC). The system can be implemented by means of a binary Bose-Einstein condensate loaded in the corresponding optical lattice. In the linear limit, the SOC opens a...

We report the coexistence and properties of stable compact localized states (CLSs) and discrete solitons (DSs) for nonlinear spinor waves on a flatband network with spin-orbit coupling (SOC). The system can be implemented by means of a binary Bose-Einstein condensate loaded in the corresponding optical lattice. In the linear limit, the SOC opens a...

The localized mode propagation in binary nonlinear kagome ribbons is investigated with the premise to ensure controlled light propagation through photonic lattice media. Particularity of the linear system characterized by the dispersionless flat band in the spectrum is the opening of new minigaps due to the "binarism." Together with the presence of...

Multicore fibers with linearly coupled cores are considered as a means of the coherent transport needed for high-capacity communication systems and high-power fiber lasers. The conditions of the existence and stability of coherent light propagation in multicore fibers with circularly arranged cores are derived. The multicore fiber is modeled by the...

Light propagation through composite photonic lattice containing a cavity bounded by the interface between two structurally different linear lattices and on-site nonlinear defect in one of them is investigated numerically. We find conditions under which dynamically stable bounded cavity modes can exist. We observe various cavity localized modes such...

An overview of the main results for light propagation and control over it in composite complex photonic lattices based on photorefractive materials is presented. Performed dynamical simulations of light propagation in composite PLs indicate the possibility of controlling optical beam propagation through these lattices by properly designing their pa...

The multicore fiber (MCF) is a physical system of high practical importance. In addition to standard exploitation, MCFs may support discrete vortices that carry orbital angular momentum suitable for spatial-division multiplexing in high-capacity fiber-optic communication systems. These discrete vortices may also be attractive for high-power laser a...

We consider two-dimensional (2D) arrays of self-organized semiconductor quantum dots (QDs) strongly interacting with electromagnetic field in the regime of Rabi oscillations. The QD array built of two-level states is modelled by two coupled systems of discrete nonlinear Schr\"{o}dinger equations. Localized modes in the form of single-peaked fundame...

Here we present a comprehensive theoretical study of a porous-film sensor of fluid in Mach–Zehnder configuration. It is found that the penetration of a fluid into the film pores causes amplitude and phase modulation of the interferometer output signal, maximizing the sensitivity at a certain value of the fluid refractive index. We define the Fisher...

We introduce a discrete model for binary spin-orbit-coupled (SOC) Bose-Einstein condensates (BEC) trapped in a deep one-dimensional optical lattice. Two different types of the couplings are considered, with spatial derivatives acting inside each species, or between the species. The discrete system with inter-site couplings dominated by the SOC, whi...

The spatiotemporal complexity induced by perturbed initial excitations through the development of modulational instability in nonlinear lattices with or without disorder, may lead to the formation of very high amplitude, localized transient structures that can be named as extreme events. We analyze the statistics of the appearance of these collecti...

We study numerically light beam propagation across uniform, linear, one-dimensional photonic lattice possessing one nonlinear defect. Depending on the strength of nonlinear defect, input beam position and phase shift, different dynamical regimes have been identified. We distinguish input parameters set for which a regime of light propagation blocka...

In this paper, we present the analysis and numerical model of absorptive gas detection by an optical evanescent-wave sensor. We investigate the influence of sensor geometry and thin-film porosity on the attenuation of guided modes caused by their interaction with the gas. We show that film porosity is a critical parameter that should be carefully o...

In this paper we study nonlinear dynamics of microtubules (MTs) relying on so-called u-model. A crucial discrete differential equation is transformed into a partial differential equation using a continuum approximation. Both the continuum and the discrete equations are solved and an excellent agreement of the results shows that MTs can be viewed as...

We study light propagation in the vicinity of nonlinear defect that is placed near the interface between disparate linear lattices. Various dynamical regimes including simultaneous excitation of different strongly localized cavity modes are observed.

In the present paper, we study nonlinear dynamics of microtubules (MTs). As an analytical method, we use semi-discrete approximation and show that localized modulated solitonic waves move along MT. This is supported by numerical analysis. Both cases with and without viscosity effects are studied.

Spatially periodic modulation of the intersite coupling in two-dimensional (2D) nonlinear lattices modifies the eigenvalue spectrum by opening mini-gaps in it. This work aims to build stable localized modes in the new bandgaps. Numerical analysis shows that single-peak and composite two- and four-peak discrete static solitons and breathers emerge a...

We investigate light localization in quasi-periodic nonlinear photonic lattices (PLs) composed of two periodic component lattices of equal lattice potential strength and incommensurate spatial periods. By including the system parameters from the experimentally realizable setup, we confirm that the light localization is a threshold determined phenom...

Multimode interferometers are coming of age both as sensors and components of quantum circuits.Here we investigate an interferometer based on a porous thinfilm sensor of refractive index of fluids. Eigenmode analysis is used to identify effective single- and multi-mode sensing regimes and the corresponding realizations of interferometer. A general...

We investigated the influence of the structural defect placed inside uniform photonic lattice on existence and dynamics of dark spatially localized defect modes. Depending on the strength of the defect and considering the lattice with defocusing saturable nonlinearity, we found two different types of dark solutions to exist. Their stability and dyn...

We investigate the stability and dynamical properties of complexes consisting of two identical vortices with topological charges S = 1 and 2 in the system of two linearly on-site-coupled two-dimensional (2D) vortices. The system is mathematically modeled by two coupled nonlinear differential-difference 2D Schrödinger equations. It is found that the...

We develop a theory for the interaction of classical light fields with an a chain of coupled quantum dots (QDs), in the strong-coupling regime, taking into account the local-field effects. The QD chain is modeled by a one-dimensional (1D) periodic array of two-level quantum particles with tunnel coupling between adjacent ones. The local-field effec...

We report that infinite and semi-infinite lattices with spatially inhomogeneous self-defocusing (SDF)\ onsite nonlinearity, whose strength increases rapidly enough toward the lattice periphery, support stable unstaggered (UnST) discrete bright solitons, which do not exist in lattices with the spatially uniform SDF nonlinearity. The UnST solitons co...

We study managing of light beam propagation by competing disorder and nonlinearity in one-dimensional disordered, nonlinear photonic lattices (PLs). The system is modeled by a paraxial time-independent Helmholtz equation, which includes the nonlinear saturable self-interacting term and the quenched or nonquenched disordered PL potential. Diverse PL...

We study normal modes propagating on top of the stable uniform background in arrays of dipolar Bose-Einstein condensate (BEC) droplets trapped in a deep optical lattice. Both the on-site mean-field dynamics of the droplets and their displacement due to the repulsive dipole-dipole interactions (DDIs) are taken into account. Dispersion relations for...

The existence and stability of spatial solitons in one-dimensional binary photonic lattices with alternating spacing and a saturable defocusing type of nonlinearity are investigated. Five types of nonlinear localized structures are found to exist: two in the mini-gap in the energy spectrum and others in the regular gap. It is proved that some of th...

Periodic patterns with doubled lattice periodicity (DPP) that originate from the modulationally unstable continuous-wave (CW)-type state are found in dipolar Bose–Einstein condensates loaded into a deep one-dimensional optical lattice. The DPP can be created in the presence of any type of contact and/or dipole–dipole (DD) interaction in the system....

Spatiotemporal complexity is induced in a two dimensional nonlinear disordered lattice through the modulational instability of an initially weakly perturbed excitation. In the course of evolution we observe the formation of transient as well as persistent localized structures, some of which have extreme magnitude. We analyze the statistics of occur...

Density-wave patterns in (quasi-) discrete media with local interactions are known to be unstable. We demonstrate that \emph{stable} double- and triple- period patterns (DPPs and TPPs), with respect to the period of the underlying lattice, exist in media with nonlocal nonlinearity. This is shown in detail for dipolar Bose-Einstein condensates (BECs...

Microtubule (MT) is a major cytoskeletal protein. Beside its mechanical role in cells it serves as a “road network” for motor proteins (kinesin and dynein) dragging different “cargos” such as vesicles and mitochondria to different sub-cellular locations. In this article we explain three models describing its nonlinear dynamics and we call them u, z...

Existence, stability, and dynamics of soliton complexes, centered at the site of a single transverse link connecting two parallel two-dimensional (2D) lattices, are investigated. The system with the onsite cubic self-focusing nonlinearity is modeled by the pair of discrete nonlinear Schrödinger equations linearly coupled at the single site. Symmetr...

Fundamental solitons pinned to the interface between three semi-infinite one-dimensional nonlinear dynamical chains, coupled at a single site, are investigated. The light propagation in the respective system with the self-attractive on-site cubic nonlinearity, which can be implemented as an array of nonlinear optical waveguides, is modeled by the s...

In order to perform a computer simulation of a large time and spatial scale system, such as a fusion plasma device and solar-terrestrial plasma, macro simulation model, where micro physics is modeled analytically or empirically, is usually used. However, kinetic effects such as wave-particle interaction play important roles in most of nonlinear pla...

The formation of unstaggered localized modes in dynamical lattices can be supported by the interplay of discreteness and nonlinearity with a finite relaxation time. In rapidly responding nonlinear media, on-site discrete solitons are stable, and their broad inter-site counterparts are marginally stable, featuring a virtually vanishing real instabil...

A hydrodynamic model of two-plasmon decay in a homogeneous plasma slab near the quarter-critical density is utilized to study the spatio-temporal evolution of the daughter electron plasma waves in plasma in the course of the instability. The influence of laser and plasma parameters on the evolution of the amplitudes of the participating waves is di...

We investigate the effects of dipole-dipole (DD) interactions on immiscibility-miscibility transitions (IMT’s) in two-component Bose-Einstein condensates (BEC’s) trapped in the harmonic-oscillator (HO) potential, with the components linearly coupled by a resonant electromagnetic field (accordingly, the components represent two different spin states...

We investigate light localization at a single phase-slip defect in one-dimensional photonic lattices, both numerically and experimentally. We demonstrate the existence of various robust linear and nonlinear localized modes in lithium niobate waveguide arrays exhibiting saturable defocusing nonlinearity.

Fundamental solitons pinned to the interface between two discrete lattices coupled at a single site are investigated. Serially and parallel-coupled identical chains (\textit{System 1} and \textit{System 2}), with the self-attractive on-site cubic nonlinearity, are considered in one dimension. In these two systems, which can be readily implemented a...

We analyse the existence, stability and dynamics of localized discrete modes with intrinsic vorticity S = 1 and S = 2 in the disc-shaped dipolar Bose-Einstein condensate loaded into a deep two-dimensional optical lattice. The condensate, which features the interplay of local contact and nonlocal dipole-dipole (DD) interactions between atoms, is mod...

A hydrodynamic model of two‐plasmon decay in a homogeneous plasma slab near the quarter‐critical density is constructed in order to gain better insight into the spatio‐temporal evolution of the daughter electron plasma waves in plasma in the course of the instability. The influence of laser and plasma parameters on the evolution of the amplitudes o...

We analyze the formation and dynamics of bright unstaggered solitons in the disk-shaped dipolar Bose-Einstein condensate, which features the interplay of contact (collisional) and long-range dipole-dipole (DD) interactions between atoms. The condensate is assumed to be trapped in a strong optical-lattice potential in the disk's plane, hence it may...