Dipolar bilayer with antiparallel polarization: A self-bound liquid

作者：Hebenstreit Martin; Rader Michael; Zillich Robert E^*

来源：Physical Review A, 2016, 93(1): 013611.

DOI：10.1103/PhysRevA.93.013611

Dipolar bilayers with antiparallel polarization, i.e., opposite polarization in the two layers, exhibit liquidlike rather than gaslike behavior. In particular, even without external pressure, a self-bound liquid droplet of constant density will form. We investigate the symmetric case of two identical layers, corresponding to a two-component Bose system with equal partial densities. The zero-temperature equation of state E(rho)/N, where rho is the total density, has a minimum, with an equilibrium density that can be adjusted by the distance d between the layers (decreasing with increasing d). The attraction necessary for a self-bound liquid comes from the interlayer dipole-dipole interaction that leads to a mediated intralayer attraction. We investigate the regime of negative pressure towards the spinodal instability, where the bilayer is unstable against infinitesimal fluctuations of the total density, confirmed by calculations of the speed of sound of total density fluctuations.

• 出版日期2016-1-12