Stabilization and Pumping of Giant Vortices in Dilute Bose–Einstein Condensates

Abstract

Recently, it was shown that giant vortices with arbitrarily large quantum numbers can possibly be created in dilute Bose-Einstein condensates by cyclically pumping vorticity into the condensate. However, multiply quantized vortices are typically dynamically unstable in harmonically trapped nonrotated condensates, which poses a serious challenge to the vortex pump procedure. In this theoretical study, we investigate how the giant vortices can be stabilized by the application of a Gaussian potential peak along the vortex core. We find that achieving dynamical stability is feasible up to high quantum numbers. To demonstrate the efficiency of the stabilization method, we simulate the adiabatic creation of an unsplit 20-quantum vortex with the vortex pump.

Free expansion of Bose-Einstein condensates with a multicharged vortex

“…In general, dissipation makes multi-charged vortices split into singly charged vortices [27,30]. However, some research groups have implemented techniques to overcome this issue, as for example: implementing a tightly focused resonant laser [31], using a blue-detuned laser beam which compensates the gravity [32], and by the application of a Gaussian potential peak along the vortex core [33].…”

Splitting of singly and doubly quantized composite vortices in two-component Bose-Einstein condensates

“…Each of these exotic splitting modes is the dominant dynamical instability of the respective stationary vortex in a wide range of intercomponent interaction strengths and relative populations of the two condensate components and should be amenable to experimental detection. Our results contribute to a better understanding of vortex physics, hydrodynamic instabilities, and two-dimensional quantum turbulence in multicomponent superfluids.The aforementioned studies of vortex splitting [23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38] were conducted for a solitary scalar BEC, which is described by a single C-valued order parameter. However, vortex physics becomes much more diverse when multiple, say K ∈ N, scalar condensates come into contact, interact with one another, and thereby constitute an K-component BEC described by a C K -valued vectorial order parameter.…”

Counterdiabatic vortex pump in spinor Bose-Einstein condensates

“…The total duration of one cycle in this scheme is only T cycle = 1.79 ms. This is significantly faster than vortex pumping relying on standard adiabatic dynamics [28][29][30][31]33].…”

“…On the other hand, a vortex with a large winding number is dynamically unstable into splitting into multiple single-quantum vortices [32], motivating faster vortex pumping. The stability of the large-winding-number states has been studied [33,34], as well as their splitting dynamics [35].…”