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The low energy continuum limit of graphene is effectively known to be modeled using Dirac equation in (2+1) dimensions. We consider the possibility of using modulated high frequency periodic driving of a two-dimension system (optical lattice) to simulate properties of rippled graphene. We suggest that the Dirac Hamiltonian in a curved background space can also be effectively simulated by a suitable driving scheme in optical lattice. The time dependent system yields, in the approximate limit of high frequency pulsing, an effective time independent Hamiltonian that governs the time evolution, except for an initial and a final kick. We use a specific form of 4-phase pulsed forcing with suitably tuned choice of modulating operators to mimic the effects of curvature. The extent of curvature is found to be directly related to $omega^{-1}$ the time period of the driving field at the leading order. We apply the method to engineer the effects of curved background space. We find that the imprint of curvilinear geometry modifies the electronic properties, such as LDOS, significantly. We suggest that this method shall be useful in studying the response of various properties of such systems to non-trivial geometry without requiring any actual physical deformations.
The thermal properties of a system, comprising of a spinless non-interacting charged particle in the presence of a constant external magnetic field and confined in a parabolic quantum well are studied. The focus has been on the effects of a topological defect, of the form of conical disclination, with regard to the thermodynamic properties of the system. We have obtained the modifications to the traditional Landau-Fock-Darwin spectrum in the presence of conical disclination. The effect of the conical kink on the degeneracy structure of the energy levels is investigated. The canonical formalism is used to compute various thermodynamic variables. The study shows an interplay between magnetic field, temperature and the degree of conicity by setting two scales for temperature corresponding to the frequency of the confining potential and the cyclotron frequency of external magnetic field. The kink parameter is found to affect the quantitative behaviour of the thermodynamic quantities. It plays a crucial role in the competition between the external magnetic field and temperature in fixing the values of the thermal response functions. This study provides an important motivation for studying similar systems, however with non trivial interactions in the presence of topological defects.
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