Regular Article

Effect of an oscillating Gaussian obstacle in a dipolar Bose-Einstein condensate

¹ Department of Physics, Bharathidasan University, Palkalaiperur Campus, Tiruchirappalli 620024, India
² Department of Physics, Savitribai Phule Pune University, Pune 411007, Maharashtra, India
³ Instituto de Física, Universidade de São Paulo, 05508-090 São Paulo, Brazil

^a e-mail: ssabari01@gmail.com
^b e-mail: kishor.bec@gmail.com

Received: 27 May 2017
Received in final form: 20 September 2017
Published online: 20 March 2018

Abstract

We study the dynamics of vortex dipoles in erbium (¹⁶⁸Er) and dysprosium (¹⁶⁴Dy) dipolar Bose-Einstein condensates (BECs) by applying an oscillating blue-detuned laser (Gaussian obstacle). For observing vortex dipoles, we solve a nonlocal Gross-Pitaevskii (GP) equation in quasi two-dimensions in real-time. We calculate the critical velocity for the nucleation of vortex dipoles in dipolar BECs with respect to dipolar interaction strengths. We also show the dynamics of the group of vortex dipoles and rarefaction pulses in dipolar BECs. In the dipolar BECs with Gaussian obstacle, we observe rarefaction pulses due to interaction of dynamically migrating vortex dipoles.