Many-body localization with synthetic gauge fields in disordered Hubbard chains

We analyze the localization properties of the disordered Hubbard model in the presence of a synthetic magnetic field. An analysis of level spacing ratio shows a clear transition from ergodic to many-body localized phase. The transition shifts to larger disorder strengths with increasing magnetic flux. Study of dynamics of local correlations and entanglement entropy indicates that charge excitations remain localized whereas spin degree of freedom gets delocalized in the presence of the synthetic flux. This residual ergodicity is enhanced by the presence of the magnetic field with dynamical observables suggesting incomplete localization at large disorder strengths. Furthermore, we examine the effect of quantum statistics on the local correlations and show that the long-time spin oscillations of a hard-core boson system are destroyed as opposed to the fermionic case.Comment: delayed version close to the published on

Out-of-equilibrium dynamics of Bose-Bose mixtures in optical lattices

We examine the quench dynamics across quantum phase transitions from a Mott insulator (MI) to a superfluid (SF) phase in a two-component bosonic mixture in an optical lattice. We show that two-component Bose mixtures exhibit qualitatively different quantum dynamics than one-component Bose gas. Besides second-order MI-SF transitions, we also investigate quench dynamics across a first-order MI-SF transition. The Bose mixtures show the critical slowing down of dynamics near the critical transition point, as proposed by the Kibble-Zurek mechanism. For MI-SF transitions with homogeneous lattice-site distributions in the MI phase, the dynamical critical exponents extracted by the power-law scaling of the proposed quantities obtained via numerical simulations are in very close agreement with the mean-field predictions.Comment: 10 pages, 11 figure

Staggered superfluid phases of dipolar bosons in two-dimensional square lattices

We study the quantum ground state of ultracold bosons in a two-dimensional square lattice. The bosons interact via the repulsive dipolar interactions and s-wave scattering. The dynamics is described by the extended Bose-Hubbard model including correlated hopping due to the dipolar interactions, the coefficients are found from the second quantized Hamiltonian using the Wannier expansion with realistic parameters. We determine the phase diagram using the Gutzwiller ansatz in the regime where the coefficients of the correlated hopping terms are negative and can interfere with the tunneling due to single-particle effects. We show that this interference gives rise to staggered superfluid and supersolid phases at vanishing kinetic energy, while we identify parameter regions at finite kinetic energy where the phases are incompressible. We compare the results with the phase diagram obtained with the cluster Gutzwiller approach and with the results found in one dimension using DMRG.Comment: version close to accepted in Phys. Rev.

A Scoping review of challenges, scope and assessment approaches of teledentistry: an Indian perspective

Context: In India, COVID-19 pandemic has limited the utilization and access to dental services owing to the risk of infections transmission. In this context, tele-dentistry could be useful but there is paucity of literature which provides guidance on the scope and challenges for using tele-dentistry in India. Aims: To identify challenges, scope and assessment approaches of tele-dentistry from an Indian perspective. Settings and Design: Scoping Review. Methods and Material: Scoping review was conducted using the Arksey and O’Malley framework. Databases were searched in July from April to August 2020. Studies concerning challenges and scope of tele-dentistry in India were included. Additionally, literature about assessment approaches used for tele-dentistry programs were also reviewed Results: A total of 64 studies were reviewed, out of which 26 articles were included in the final review. Scoping review reveled that tele-dentistry can act as a seamless tool for diagnosing, training and screening. Few studies suggested the relevance of smartphone technology for specialist consultations and proper diagnosis. Majority of studies revealed shortage of basic infrastructure as a major challenge for tele-dentistry in India. Assessment studies were mainly focused on economic perspective and cost-effectiveness of the programs. Conclusions: This review provide guidance for using tele-dentistry in India. It is also reflected that there is a need for further research about the assessment of tele-dentistry in terms of safety, clinical outcomes, and patient perception

Discovery of a New Class of Natural Product-Inspired Quinazolinone Hybrid as Potent Antileishmanial agents

The high potential of quinazolinone containing natural products and their derivatives in medicinal chemistry led us to discover four novel series of 53 compounds of quinazolinone based on the concept of molecular hybridization. Most of the synthesized analogues exhibited potent leishmanicidal activity against intracellular amastigotes (IC₅₀ from 0.65 ± 0.2 to 7.76 ± 2.1 μM) as compared to miltefosine (IC₅₀ = 8.4 ± 2.1 μM) and nontoxic toward the J-774A.1 cell line and Vero cells. Moreover, activation of Th1 type and suppression of Th2 type immune responses and induction in nitric oxide generation proved that <b>8a</b> and <b>8g</b> induce murine macrophages to prevent survival of parasites. Compounds <b>8a</b> and <b>8g</b> exhibited significant in vivo inhibition of parasite 73.15 ± 12.69% and 80.93 ± 10.50% against Leishmania donovani/hamster model. Our results indicate that compounds <b>8a</b>, <b>8g</b>, and <b>9f</b> represent a new structural lead for this serious and neglected disease