publications

2024

1. Competing order in two-band Bose-Hubbard chains with extended-range interactions

   Yuma Watanabe , Utso Bhattacharya , Ravindra W. Chhajlany , and 3 more authors

   Physical Review B, Mar 2024

   Publisher: American Physical Society

   Abs

   Motivated by the recent progress in realizing and controlling extended Bose-Hubbard systems using excitonic or atomic devices, the present Letter theoretically investigates the case of a two-band Bose-Hubbard chain with nearest-neighbor interactions. Specifically, this study concentrates on the scenario where, due to the interactions, one band supports a density-wave phase, i.e., a correlated insulating phase with spontaneous breaking of translational symmetry in the lattice, while the other band supports superfluid behavior. Using the density matrix renormalization group method, we show that supersolid order can emerge from such a combination, that is, an elusive quantum state that combines crystalline order with long-range phase coherence. Depending on the filling of the bands and the interband interaction strength, the supersolid phase competes with phase-separation, superfluid order, or Mott insulating density-wave order. As a possible setup to observe supersolidity, we propose the combination of a lower band supporting density-wave order and a thermally excited band that supports superfluidity due to weaker lattice confinement.

2. Eigenstate thermalization and its breakdown in quantum spin chains with inhomogeneous interactions

   Ding-Zu Wang , Hao Zhu , Jian Cui , and 5 more authors

   Physical Review B, Jan 2024

   Publisher: American Physical Society

   Abs

   The eigenstate thermalization hypothesis (ETH) is a successful theory that establishes the criteria for ergodicity and thermalization in isolated quantum many-body systems. In this work, we investigate the thermalization properties of a spin-1/2 XXZ chain with linearly inhomogeneous interactions. We demonstrate that introduction of the inhomogeneous interactions leads to an onset of quantum chaos and thermalization, which, however, becomes inhibited for sufficiently strong inhomogeneity. To exhibit ETH, and to display its breakdown upon varying the strength of interactions, we probe statistics of energy levels and properties of matrix elements of local observables in eigenstates of the inhomogeneous XXZ spin chain. Moreover, we investigate the dynamics of the entanglement entropy and the survival probability which further evidence the thermalization and its breakdown in the considered model. We outline a way to experimentally realize the XXZ chain with linearly inhomogeneous interactions in systems of ultracold atoms. Our results highlight a mechanism of emergence of ETH due to insertion of inhomogeneities in an otherwise integrable system and illustrate the arrest of quantum dynamics in the presence of strong interactions.

3. Stabilization of Hubbard-Thouless pumps through nonlocal fermionic repulsion

   Javier Argüello-Luengo , Manfred J. Mark , Francesca Ferlaino , and 3 more authors

   Quantum, Mar 2024

   Publisher: Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften

   Abs

   Javier Argüello-Luengo, Manfred J. Mark, Francesca Ferlaino, Maciej Lewenstein, Luca Barbiero, and Sergi Julià-Farré, Quantum 8, 1285 (2024). Thouless pumping represents a powerful concept to probe quantized topological invariants in quantum systems. We explore this mechanism in a generalized Rice-Mele Fermi-Hubbard model characte…

2023

1. Entanglement and squeezing of the optical field modes in high harmonic generation

   Philipp Stammer , Javier Rivera-Dean , Andrew S. Maxwell , and 5 more authors

   Oct 2023

   arXiv:2310.15030 [physics, physics:quant-ph]

   Abs

   Squeezing of optical fields, used as a powerful resource for many applications, and the radiation properties in the process of high harmonic generation have thus far been considered separately. In this Letter, we want to clarify that the joint quantum state of all the optical field modes in the process of high harmonic generation is in general entangled and squeezed. We show that this is already the case in the simplest scenario of driving uncorrelated atoms by a classical laser light field. The previous observation of product coherent states after the high harmonic generation process is a consequence of the assumption that the ground state depletion can be neglected, which is related to vanishing dipole moment correlations. Furthermore, we analyze how the resulting quadrature squeezing in the fundamental laser mode after the interaction can be controlled and explicitly show that all field modes are entangled.

2. Synthetic dimensions for topological and quantum phases: Perspective

   Javier Argüello-Luengo , Utso Bhattacharya , Alessio Celi , and 8 more authors

   Oct 2023

   arXiv:2310.19549 [cond-mat, physics:hep-lat, physics:physics, physics:quant-ph]

   Abs

   In this Perspective article we report on recent progress on studies of synthetic dimensions, mostly, but not only, based on the research realized around the Barcelona groups (ICFO, UAB), Donostia (DIPC), Pozna}’n (UAM), Krak}’ow (UJ), and Allahabad (HRI). The concept of synthetic dimensions works particularly well in atomic physics, quantum optics, and photonics, where the internal degrees of freedom (Zeeman sublevels of the ground state, metastable excited states, or motional states for atoms, and angular momentum states or transverse modes for photons) provide the synthetic space. We describe our attempts to design quantum simulators with synthetic dimensions, to mimic curved spaces, artificial gauge fields, lattice gauge theories, twistronics, quantum random walks, and more.

2022

1. Optomechanical strong coupling between a single photon and a single atom

   Javier Argüello-Luengo , and Darrick E. Chang

   New Journal of Physics, Oct 2022

   Publisher: IOP Publishing
2. A generalized multi-scale entanglement renormalization ansatz: more accurate conformal data from a critical lattice model

   Javier Argüello-Luengo , Ashley Milsted , and Guifre Vidal

   arXiv preprint arXiv:2212.06740, Oct 2022
3. Tuning long-range fermion-mediated interactions in cold-atom quantum simulators

   Javier Argüello-Luengo , Alejandro González-Tudela , and Daniel González-Cuadra

   Physical Review Letters, Oct 2022

   Publisher: APS

2021

1. Engineering analog quantum chemistry Hamiltonians using cold atoms in optical lattices

   Javier Argüello-Luengo , Tao Shi , and Alejandro González-Tudela

   Physical Review A, Apr 2021

   Abs

   Using quantum systems to efficiently solve quantum chemistry problems is one of the long-sought applications of near-future quantum technologies. In a recent work [J. Argüello-Luengo et al., Nature (London) 574, 215 (2019)], ultracold fermionic atoms have been proposed for this purpose by showing us how to simulate in an analog way the quantum chemistry Hamiltonian projected in a lattice basis set. Here, we continue exploring this path and go beyond these results in several ways. First, we numerically benchmark the working conditions of the analog simulator and find less demanding experimental setups where chemistry-like behavior in three dimensions can still be observed. We also provide a deeper understanding of the errors of the simulation appearing due to discretization and finite-size effects and provide a way to mitigate them. Finally, we benchmark the simulator characterizing the behavior of two-electron atoms (He) and molecules (HeH+) beyond the example considered in the original work.

2. Simuladores cuánticos analógicos: Una herramienta para entender la materia que nos rodea

   Javier Argüello-Luengo , and Alejandro González-Tudela

   Revista Española de Física, Apr 2021

2020

1. Quantum simulation of two-dimensional quantum chemistry in optical lattices

   Javier Argüello-Luengo , Alejandro González-Tudela , Tao Shi , and 2 more authors

   Physical Review Research, Apr 2020

   Publisher: APS

2019

1. Analogue quantum chemistry simulation

   Javier Argüello-Luengo , Alejandro González-Tudela , Tao Shi , and 2 more authors

   Nature, Apr 2019

   url_Paper: https://arxiv.org/pdf/1807.09228.pdf

2015

1. Heat asymmetries in nanoscale conductors: The role of decoherence and inelasticity

   Javier Argüello-Luengo , David Sánchez , and Rosa López

   Physical Review B, Apr 2015

   Publisher: APS