arXiv subjects

Mrinal Kanti Giri

Publications and source records attributed to Mrinal Kanti Giri.

9 recordsLinked to original sources

arXiv2026

Quantum Simulation of Detuning-Controlled Proximity-Induced Localization and Reentrant Delocalization in a Quasiperiodic Ladder

We demonstrate proximity-induced localization and re-entrant delocalization in a detuned quasiperiodic ladder. In the weak-quasiperiodic regime, where uncoupled Aubry-André chains are extended, a staggered detuning applied to only one leg induces localization in the neighboring leg through inter-leg hybridization. With further increasing detuning, the pure chain re-enters a delocalized regime, producing a delocalized-localized-delocalized sequence without directly modifying its quasiperiodic potential. We identify these regimes using static localization diagnostics and demonstrate experimentally accessible dynamical signatures on IBM Quantum hardware: strongly suppressed wavefunction spreading in the proximity-localized regime and its re-entrant recovery at larger detuning. These results establish leg-selective detuning as a programmable control knob for inducing and reversing localization in coupled quasiperiodic systems.

cond-mat.quant-gas↗

arXiv2026

Digital Quantum Simulation of Flat-Band and All-Bands-Flat Dynamics for Tunable Quantum Transport

Flat-band systems offer a uniquely powerful tool for quantum control in dynamics due to their characteristic feature of having a dispersionless energy band. Simulating such highly sensitive systems on current digital quantum computers is a challenging task, due to the intrinsic limitations of the noisy intermediate-scale quantum (NISQ) devices. Here we present high-fidelity digital quantum simulations of flat-band (FB) and all-bands-flat (ABF) lattices, using an advanced tensor network based variational optimization approach to compress the circuit depth. With the compressed quantum circuits, we first explore single-particle dynamics and observe two distinct behaviours: strong localization in ABF lattices and delocalization in FB lattices. By integrating FB and ABF lattices into a one-dimensional hybrid structure, we achieve controllable quantum transport, where the ABF lattice acts as a quantum switch. Extending to two-particle dynamics, we show that transport remains controllable by tuning the hopping amplitude alone, even in the presence of interactions. These results establish flat-band engineered systems as a promising pathway for scalable control of quantum transport in emerging quantum technologies, with potential applications in qubit isolation, particle trapping, and state transfer.

quant-ph↗

arXiv2025

Flux enhanced localization and reentrant delocalization in the quench dynamics of two interacting bosons on a Bose-Hubbard ladder

We study the quench dynamics of two bosons possessing onsite repulsive interaction on a two-leg ladder and show that the presence of uniform flux piercing through the plaquettes of the ladder favors the localization of the bound states in the dynamics. We find that when the two bosons are symmetrically initialized on the edge rung of the ladder, they tend to edge-localize in their quantum walk - a phenomenon which is not possible in the absence of flux. On the other hand, when the bosons are initialized on the bulk rung they never localize and exhibit linear spreading in their quantum walk. Interestingly, however, we find that in the later case a finite flux favours localization of the bulk bound states in the presence of sufficiently weak quasiperiodic disorder which is otherwise insufficient to localize the particles in the absence of flux. In both the cases, we obtain that the localization in the dynamics strongly depends on the combined effect of the flux and interaction strengths, as a result which we obtain a signature of re-entrant delocalization as a function of flux (interaction) for fixed interaction (flux) strengths.

cond-mat.quant-gas↗

arXiv2025

Flux induced re-entrant dynamics in the quantum walk of interacting bosons

We study the QW of two interacting bosons on a two-leg ladder lattice in the presence of an artificial magnetic field. By considering an uniform flux piercing through the ladder, we show that in the limit of strong onsite repulsion and dominant rung-hopping, an initially slow dynamics becomes fast, then slow and fast again with increase in the flux strength indicating a re-entrant dynamics. This unusual behaviour is found to be associated with the formation, breaking and reformation of a bound pair state along the rung of the ladder. In addition to this we also find a re-entrant behaviour in the chiral dynamics where the chirality in the system first increases and then decreases with increase in interaction. We establish this unusual re-entrant behaviour in the dynamics by analysing the radial velocity, spreading of correlation, center-of-mass shearing and energy band diagrams.

cond-mat.quant-gas↗

arXiv2024

Realizing Topological Quantum Walks on NISQ Digital Quantum Computer

We study the quantum walk on the off-diagonal Aubry-André-Harper (AAH) lattice with periodic modulation using a digital quantum computer. We investigate various initial states at the single-particle level, considering different hopping modulation strengths and phase factors. Initiating the quantum walk with a particle at the lattice edge reveals the robustness of the edge state, attributed to the topological nature of the AAH model, and displays the influence of the phase factor on this edge state. On the other hand, when the quantum walk begins with a particle in the lattice bulk, we observe a repulsion of the bulk walker from the edge, especially under strong hopping modulation. Furthermore, we extend our investigation to the quantum walk of two particles with nearest-neighbour (NN) interaction. We show the repulsion effect in the quantum walk when two walkers originate from the edge and bulk of the lattice due to the interaction. Additionally, when two particles are positioned at NN sites and subjected to strong hopping modulation strength, they exhibit localization in the presence of interaction. We analyze these phenomena by examining physical quantities such as density evolution, two-particle correlation, and participation entropy, and discuss their potential applications in quantum technologies.

quant-ph↗

arXiv2023

Quantum phases of constrained bosons on a two-leg Bose-Hubbard ladder

Bosons in periodic potentials with very strong local interactions, known as the constrained bosons often exhibit interesting physical behavior. We investigate the ground state properties of a two-leg Bose-Hubbard ladder by imposing three-body constraint in one leg and hardcore constraint in the other. By using the cluster-mean-field theory approximation and the density matrix renormalization group method, we show that at unit filling, for strong two-body attraction among the three-body constrained bosons, the system becomes a gapped pair-Mott insulator where all the bosons form strong bound pairs and occupy the leg with three-body constraint. With increase in hopping strength this pair-Mott insulator phase undergoes a phase transition to the gapless superfluid phase for equal leg and rung hopping strengths. However, when the rung hopping is stronger compared to the leg hopping, we obtain a crossover to another gapped phase which is called the rung-Mott insulator phase where the bosons prefer to delocalize on the rungs than the legs. By moving away from unit filling, the system remains in the superfluid phase except for a small region below the gapped phase where a pair superfluid phase is stabilized in the regime of strong attractive interaction. We further extend our studies by considering three-body constraint on both the legs and find that the crossover from the gapped to gapped phase does not occur rather the system undergoes a transition from a pair-rung-Mott insulator phase to the superfluid phase at unit filling. Moreover, in this case we find the signature of the pair superfluid phase on either sides of this gapped phase.

cond-mat.quant-gas↗

arXiv2022

Signatures of non-trivial pairing in the quantum walk of two-component bosons

Nearest neighbour bosons possessing only onsite interactions do not form onsite bound pairs in their quantum walk due to fermionization. We obtain signatures of non-trivial onsite pairing in the quantum walk of strongly interacting two component bosons in a one dimensional lattice. By considering an initial state with particles from different components located at the nearest-neighbour sites in the central region of the lattice, we show that in the dynamical evolution of the system, competing intra- and inter-component onsite repulsion leads to the formation of onsite inter-component bound states. We find that when the total number of particles is three, an inter-component pair is favoured in the limit of equal intra- and inter-component interaction strengths. However, when two bosons from each species are considered, inter-component pairs and trimer are favoured depending on the ratios of the intra- and inter-component interactions. In both the cases, we find that the quantum walks exhibit a re-entrant behaviour as a function of inter-component interaction.

cond-mat.quant-gas↗

arXiv2022

Emergence of multiple localization transitions in a one-dimensional quasiperiodic lattice

Low dimensional quasiperiodic systems exhibit localization transitions by turning all quantum states localized after a critical quasidisorder. While certain systems with modified or constrained quasiperiodic potential undergo multiple localization transitions in one dimension, we predict an emergence of multiple localization transitions without directly imposing any constraints on the quasiperiodic potential. By considering a one-dimensional system described by the Aubry-Andŕe (AA) model, we show that an additional staggered onsite potential can drive the system through a series of localization transitions as a function of the staggered potential. Interestingly, we find that the number of localization transitions strongly depends on the strength of the quasiperiodic potential. Moreover, we obtain the signatures of these localization transitions in the expansion dynamics and propose an experimental scheme for their detection in the quantum gas experiment.

cond-mat.quant-gas↗

arXiv2021

Two component quantum walk in one-dimensional lattice with hopping imbalance

We investigate the two-component quantum walk in one-dimensional lattice. We show that the inter-component interaction strength together with the hopping imbalance between the components exhibit distinct features in the quantum walk for different initial states. When the walkers are initially on the same site, both the slow and fast particles perform independent particle quantum walks when the interaction between them is weak. However, stronger inter-particle interactions result in quantum walks by the repulsively bound pair formed between the two particles. For different initial states when the walkers are on different sites initially, the quantum walk performed by the slow particle is almost independent of that of the fast particle, which exhibits reflected and transmitted components across the particle with large hopping strength for weak interactions. Beyond a critical value of the interaction strength, the wave function of the fast particle ceases to penetrate through the slow particle signalling a spatial phase separation. However, when the two particles are initially at the two opposite edges of the lattice, then the interaction facilitates the complete reflection of both of them from each other. We analyze the above mentioned features by examining various physical quantities such as the on-site density evolution, two-particle correlation functions and transmission coefficients.

cond-mat.quant-gas↗