Two-Dimensional Bright Solitons in Dipolar BEC with Tilted Dipoles

Abstract

Recent experiments on atomic dipoles and polar molecules have shown that dipole-dipole interactions play a very significant role in the physics of ultracold quantum gases. It is now known that due to their long-range and anisotropic nature, dipole-dipole interactions may stabilize multi-dimensional solitons in dipolar BECs, especially two-dimensional bright solitons. Contrary to the 2D and 3D short range interacting condensates, which collapse in the presence of unstable phonons, phonon instability in 2D dipolar condensates results in the transient formation of a gas of inelastic 2D bright solitons that eventually fuse to form a larger bright soliton. Previous studies on 2D bright solitons in dipolar BECs have involved dipoles aligned either perpendicular or parallel to the 2D plane containing the condensate. However, their experimental realization still remains a huge challenge. In this thesis, we explore a new configuration by tilting the dipoles to an angle with respect to the axis normal to the 2D plane. This controls the anisotropy and allows a better control in the tuning of interaction parameters, thereby increasing the possibility of experimentally observing two-dimensional bright solitons in dipolar condensates of atoms such as Chromium, Erbium and Dysprosium.