Quantum-Granularity Effect in the Formation of Supermixed Solitons in Ring Lattices

Abstract

We investigate a notable class of states peculiar to a bosonic binary mixture featuring repulsive intraspecies and attractive interspecies couplings. We evidence that, for small values of the hopping amplitudes, one can access particular regimes marked by the fact that the interwell boson transfer occurs in a jerky fashion. This property is shown to be responsible for the emergence of a staircase-like structure in the phase diagram of a mixture confined in a ring trimer and to strongly resemble the mechanism of the superfluid-Mott insulator transition. Under certain conditions, in fact, we show that it is possible to interpret the interspecies attraction as an effective chemical potential and the supermixed soliton as an effective particle reservoir. Our investigation is developed both within a fully quantum approach based on the analysis of several quantum indicators and by means of a simple analytical approximation scheme capable of capturing the essential features of this ultraquantum effect. arXiv:1912.04980v2 [cond-mat.quant-gas] 3 Jan 2020

Ground-State Properties and Phase Separation of Binary Mixtures in Mesoscopic Ring Lattices

“…The architecture of this region is then expected to be really complex and to feature manifold ways to reach the full-demixing regime whose recognition is far from being trivial (see, e.g., the four-well phase diagrams for a preliminary example). This richness strongly resembles the scenario of ground-state configurations of quantum emulsions [ 15 , 45 ] and suggests the observation of quantum-granularity effects triggered by the interplay of strong effective interactions , weak hopping amplitudes and fractional values of [ 46 ]. These aspects will be further explored in a separate paper.…”

Harnessing currents of particles for spectroscopy in small-ring lattices with binary mixtures

“…Currently, many-body states can be experimentally analyzed using a wide number of techniques that range from momentum distribution [4], noise correlations [5,6], rf-spectroscopy [3], Bragg spectroscoy [7] and lattice modulation spectroscopy [8,9]. This scenario becomes richer in binary mixtures [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26], where the interplay between species leads to novel and exotic quantum phases [26,27]. Thus, the development of a new experimental technique for the characterization of many-body ground states could be of great benefit for the entire field.…”