On the formation of stripe, sigma, and honeycomb phases in a core–corona system

Abstract

Using Monte Carlo simulations and free-energy calculations, we investigate the phase behaviour of a two-dimensional core-corona system. We model this system as particles consisting of an impenetrable hard core of diameter σ surrounded by a purely repulsive soft corona of diameter δ = 1.95σ. At low densities, we observe the spontaneous formation of a phase with a stripe texture as well as a honeycomb-like phase driven by both energy and entropy considerations. At high densities, we find that a two-dimensional analogue of the periodic sigma phase, considered as an approximant of dodecagonal quasicrystals, is energetically stabilised with respect to two distinct dodecagonal quasicrystals, namely, a square-triangle tiling and a square-triangle-shield tiling. We also find the formation of stable hexagonal phases at three distinct density ranges, which are energetically driven, i.e. by minimising the overlap of coronas. Furthermore, our calculations show that the low-density dodecagonal quasicrystal that was previously reported by Dotera et al., [Nature, 2014, 506, 208] is kinetically formed in the coexistence region between the honeycomb and the medium-density hexagonal phase.

Sequential phase transitions and transient structured fluctuations in two-dimensional systems with a high-density Kagome lattice phase

“…1, is very different from the shape of the core-corona potential, and the argument vis a vis string stabilization by minimization of the potential energy is harder to make. Nevertheless, the arrangement of particles in the Truskett system string phase appears to be sensibly the same as that in the core-corona system strings phase [3]. A difference is that the strings in the Truskett system span the simulation cell at all densities whereas those in the core-corona system start as small chains that, with increasing density, grow to span the simulation cell.…”

“…The formation of a string phase in a 2D system has been reported for several different monotonic repulsive central pair potentials. For example, the 2D system with a hard disc plus rectangular step repulsion (so-called core-corona potential), studied by Pattabhiraman and Dijkstra [3], exhibits a string phase with overlapping coronas of nearest neighbor particles on the same string and no overlap of coronas of particles on different neighbor strings. In this case, with discontinuities in the pair potential at the core and at the edge of the corona, there is a convincing argument that string formation is accounted for by minimization of the system potential energy.…”

“…Does the spectrum of transient ordered fluctuations in the liquid phase of a system composed of particles whose direct interaction is a monotonic soft isotropic repulsive pair potential that supports many different ordered solid phases, differ from that in the hard disk liquid? 3 4. What transient ordered fluctuations in the liquid are associated with a transition from the liquid state to a solid with an open lattice, e.g.…”

“…Answers to questions (3) and (4) are related via our definition of a transient ordered fluctuation. Briefly put, we identify an ordered transient fluctuation as a symmetric configuration of a small number of particles whose diffraction pattern consists of discrete Bragg peaks.…”

Lattice and quintic nonlinearity induced stripe phase in Bose–Einstein condensate under non-inertial and inertial motion

“…Stripe phases are also well-known in high-temperature superconductivity, where it arises due to the interplay between antiferromagnetic interactions among the magnetic ions and the Coulomb interactions between the carriers [28]. The stripe phase has also been predicted in Bose-Hubbard model in a triangular optical lattice [29], quantum Hall system [30], core-corona system [31], Harper-Hofstadter-Mott model [32,33] etc.…”