Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:1510.06599 · Physical Review A

Mean-field predictions for a dipolar Bose-Einstein condensate with Dy164

Damir Zajec, Günter Wunner

Published Nov 12, 2015• 2 citations
arXivHTMLPDF

Abstract

Dipolar Bose-Einstein condensates are systems well suited for the investigation of effects caused by the nonlocal and anisotropic dipole-dipole interaction. In this paper we are interested in properties which are directly connected to the realization of a condensate with $^{164}\mathrm{Dy}$, such as stability and phase diagrams. Additionally, we study the expansion of dipolar condensates and find signatures of the dipole-dipole interaction in terms of structured states and a deviation of the well-known inversion of the aspect ratio of the cloud during a time of flight. Our analysis is based on the extended Gross-Pitaevskii equation, which we solve numerically exactly on a grid by means of an imaginary- and real-time evolution.

DOI
10.1103/physreva.92.053609

Related papers

Dipolar Bose-Einstein condensates in triple-well potentials

Rüdiger Fortanier, Damir Zajec, Jörg Main

Abstract. Dipolar Bose-Einstein condensates in triple-well potentials are well-suited model systems for periodic optical potentials with important contributions of the non-local and anisotropic dipole-dipole interaction, which show a variety of effects such as self-organisation and formation of patterns. We address here a macroscopic sample of dipolar bosons in the mean-field limit. This work is based on the Gross-Pitaevskii description of dipolar condensates in triple-well potentials by Peter et al 2012 J. Phys. B: At. Mol. Opt. Phys. 45 225302. Our analysis goes beyond the calculation of ground states presented there and clarifies the role of excited and metastable states in such systems. In particular, we find the formation of phases originating from the interplay of several states with distinct stability properties. As some of the phases are formed by metastable states special attention is paid to the characteristics of phase transitions in real-time and the dynamical stabilisation of the condensate.

•Sep 1, 2015•8 citations

Dipolar Bose–Einstein condensates in triple-well potentials

Rüdiger Fortanier, Damir Zajec, Jörg Main +1 more

Dipolar Bose-Einstein condensates in triple-well potentials are well-suited model systems for periodic optical potentials with important contributions of the non-local and anisotropic dipole-dipole interaction, which show a variety of effects such as self-organisation and formation of patterns. We address here a macroscopic sample of dipolar bosons in the mean-field limit. This work is based on the Gross-Pitaevskii description of dipolar condensates in triple-well potentials by Peter et al 2012 J. Phys. B: At. Mol. Opt. Phys. 45 225302. Our analysis goes beyond the calculation of ground states presented there and clarifies the role of excited and metastable states in such systems. In particular, we find the formation of phases originating from the interplay of several states with distinct stability properties. As some of the phases are formed by metastable states special attention is paid to the characteristics of phase transitions in real-time and the dynamical stabilisation of the condensate.

arXiv:1310.3046•Journal of Physics B Atomic Molecular and Optical Physics•Nov 7, 2013•8 citations

Bose–Einstein condensates with long-range interactions

Paulsamy Muruganandam, Ramaswamy Radha

Chapter 8 is devoted to the analysis of dipolar Bose–Einstein condensates with long-range anisotropic tunable dipole–dipole interactions, using mean-field Gross–Pitaevskii equations in one-, two-, and three-dimensional traps. Split-step Crank–Nicolson method, Gaussian variational approach, and Thomas–Fermi approximations are applied to study ground-state properties, nonlinear excitations, and stability across trap geometries.

Institute of Physics eBooks•Nov 1, 2025•0 citations

Droplet formation in a Bose-Einstein condensate with strong dipole-dipole interaction

Kui-Tian Xi, Hiroki Saito

Motivated by the recent experiment [H. Kadau et al., arXiv:1508.05007], we study roton instability and droplet formation in a Bose-Einstein condensate of $^{164}\mathrm{Dy}$ atoms with strong magnetic dipole-dipole interaction. We numerically solve the cubic-quintic Gross-Pitaevskii equation with dipole-dipole interaction, and show that the three-body interaction plays a significant role in the formation of droplet patterns. We numerically demonstrate the formation of droplet patterns and crystalline structures, decay of droplets, and hysteresis behavior, which are in good agreement with the experiment. Our numerical simulations provide the first prediction on the values of the three-body interaction in a $^{164}\mathrm{Dy}$ Bose-Einstein condensate. We also predict that the droplets remain stable during the time-of-flight expansion. From our results, further experiments investigating the three-body interaction in dipolar quantum gases are required.

arXiv:1510.07842•Physical Review A•Jan 15, 2016•79 citations

Variational approaches to dipolar Bose-Einstein condensates

Rüdiger Fortanier

In this work several aspects of dipolar Bose-Einstein condensates are investigated. These condensates have attracted much interest since their experimental realization and offer the chance to explore the novel, fascinating, and sometimes unexpected physics originating from the dipole-dipole interaction. For the theoretical description the time-dependent variational principle with an ansatz of coupled Gaussian wave packets is applied to the analysis of this form of matter. In order to describe physical systems, where the shape of the condensate wave function cannot be approximated adequately by origin-centered Gaussian functions, translational and rotational degrees of freedom of the particular wave packets are included. This provides not only a full-fledged alternative method to full-numerical grid calculations that are demanding in computation time, used for the determination of ground states and investigation of the real-time dynamics, but also allows for the calculation of excited states and the examination of stability properties and offers the possibility for a deeper physical understanding of dipolar condensates. The variational method is applied to three different physical systems. In the first one anisotropic quasi-two-dimensional solitons are investigated. Ground states and small excitations are presented and the full flexibility of the approach is utilized in the simulation of the collision of two solitons. Thereby simulations of collisions are performed, where initially the solitons are in the repelling side-by-side configuration and move towards each other with a specific momentum. It is shown that the results are in excellent agreement with full-numerical grid calculations. Collisions with various initial parameters such as the initial momentum and impact factor are performed, allowing to classify the qualitative interactions of two solitons and illuminating the effects of the solitons' two-dimensional nature on the collision process. In the second system dipolar Bose-Einstein condensates in a triple-well potential are investigated. This constitutes a well-suited model system for periodic optical potentials with important contributions of the non-local and anisotropic dipole-dipole interaction, which show a variety of effects such as self-organization and formation of patterns. Here, a macroscopic sample of dipolar bosons in the mean-field limit is addressed. The analysis goes beyond the calculation of ground states and clarifies the role of excited and metastable states in such systems. In particular, the formation of phases is found to originate from the interplay of several states with distinct stability properties. As some of the phases are formed by metastable states, special attention is paid to the characteristics of phase transitions in real time and the dynamical stabilization of the condensate. The dynamical simulations that support these results, constitute a way for an experimental observation of these findings. The third physical application is an open quantum system. Here, an external potential models gain and loss of particles and features parity with simultaneous time-reversal symmetry. For these dipolar condensates real eigenvalues of the nonlinear Hamiltonian are found, preserving the PT-symmetry of the external potential, as well as states that break this symmetry. A detailed stability analysis of these, in general complex states, is performed. The comparison with a similar system featuring a non-dipolar condensate demonstrates the role of the dipolar interaction for novel effects. Furthermore, the real-time dynamics is investigated, which reveals, among other effects, long-living oscillations of the two wells' population.

•Jan 1, 2014•3 citations

Mean-field regime of trapped dipolar Bose-Einstein condensates in one and two dimensions

Yongyong Cai, Matthias Rosenkranz, Zhen Lei +1 more

We derive rigorous one- and two-dimensional mean-field equations for cigar- and pancake-shaped dipolar Bose-Einstein condensates with arbitrary polarization angle. We show how the dipolar interaction modifies the contact interaction of the strongly confined atoms. In addition, our equations introduce a nonlocal potential, which is anisotropic for pancake-shaped condensates. We propose to observe this anisotropy via measurement of the condensate aspect ratio. We also derive analytically approximate density profiles from our equations. Both the numerical solutions of our reduced mean-field equations and the analytical density profiles agree well with numerical solutions of the full Gross-Pitaevskii equation while being more efficient to compute.

arXiv:1006.4950•Physical Review A•Oct 26, 2010•92 citations
Dipolar Bose-Einstein condensates are systems well suited for the investigation of effects caused by the nonlocal and anisotropic dipole-dipole interaction. In this paper we are interested in properties which are directly connected to the realization of a condensate with 164Dy^{164}\mathrm{Dy}164Dy, such as stability and phase diagrams. Additionally, we study the expansion of dipolar condensates and find signatures of the dipole-dipole interaction in terms of structured states and a deviation of the well-known inversion of the aspect ratio of the cloud during a time of flight. Our analysis is based on the extended Gross-Pitaevskii equation, which we solve numerically exactly on a grid by means of an imaginary- and real-time evolution.
Abstract. Dipolar Bose-Einstein condensates in triple-well potentials are well-suited model systems for periodic optical potentials with important contributions of the non-local and anisotropic dipole-dipole interaction, which show a variety of effects such as self-organisation and formation of patterns. We address here a macroscopic sample of dipolar bosons in the mean-field limit. This work is based on the Gross-Pitaevskii description of dipolar condensates in triple-well potentials by Peter et al 2012 J. Phys. B: At. Mol. Opt. Phys. 45 225302. Our analysis goes beyond the calculation of ground states presented there and clarifies the role of excited and metastable states in such systems. In particular, we find the formation of phases originating from the interplay of several states with distinct stability properties. As some of the phases are formed by metastable states special attention is paid to the characteristics of phase transitions in real-time and the dynamical stabilisation of the condensate.
Dipolar Bose-Einstein condensates in triple-well potentials are well-suited model systems for periodic optical potentials with important contributions of the non-local and anisotropic dipole-dipole interaction, which show a variety of effects such as self-organisation and formation of patterns. We address here a macroscopic sample of dipolar bosons in the mean-field limit. This work is based on the Gross-Pitaevskii description of dipolar condensates in triple-well potentials by Peter et al 2012 J. Phys. B: At. Mol. Opt. Phys. 45 225302. Our analysis goes beyond the calculation of ground states presented there and clarifies the role of excited and metastable states in such systems. In particular, we find the formation of phases originating from the interplay of several states with distinct stability properties. As some of the phases are formed by metastable states special attention is paid to the characteristics of phase transitions in real-time and the dynamical stabilisation of the condensate.
Motivated by the recent experiment [H. Kadau et al., arXiv:1508.05007], we study roton instability and droplet formation in a Bose-Einstein condensate of 164Dy^{164}\mathrm{Dy}164Dy atoms with strong magnetic dipole-dipole interaction. We numerically solve the cubic-quintic Gross-Pitaevskii equation with dipole-dipole interaction, and show that the three-body interaction plays a significant role in the formation of droplet patterns. We numerically demonstrate the formation of droplet patterns and crystalline structures, decay of droplets, and hysteresis behavior, which are in good agreement with the experiment. Our numerical simulations provide the first prediction on the values of the three-body interaction in a 164Dy^{164}\mathrm{Dy}164Dy Bose-Einstein condensate. We also predict that the droplets remain stable during the time-of-flight expansion. From our results, further experiments investigating the three-body interaction in dipolar quantum gases are required.
In this work several aspects of dipolar Bose-Einstein condensates are investigated. These condensates have attracted much interest since their experimental realization and offer the chance to explore the novel, fascinating, and sometimes unexpected physics originating from the dipole-dipole interaction. For the theoretical description the time-dependent variational principle with an ansatz of coupled Gaussian wave packets is applied to the analysis of this form of matter. In order to describe physical systems, where the shape of the condensate wave function cannot be approximated adequately by origin-centered Gaussian functions, translational and rotational degrees of freedom of the particular wave packets are included. This provides not only a full-fledged alternative method to full-numerical grid calculations that are demanding in computation time, used for the determination of ground states and investigation of the real-time dynamics, but also allows for the calculation of excited states and the examination of stability properties and offers the possibility for a deeper physical understanding of dipolar condensates. The variational method is applied to three different physical systems. In the first one anisotropic quasi-two-dimensional solitons are investigated. Ground states and small excitations are presented and the full flexibility of the approach is utilized in the simulation of the collision of two solitons. Thereby simulations of collisions are performed, where initially the solitons are in the repelling side-by-side configuration and move towards each other with a specific momentum. It is shown that the results are in excellent agreement with full-numerical grid calculations. Collisions with various initial parameters such as the initial momentum and impact factor are performed, allowing to classify the qualitative interactions of two solitons and illuminating the effects of the solitons' two-dimensional nature on the collision process. In the second system dipolar Bose-Einstein condensates in a triple-well potential are investigated. This constitutes a well-suited model system for periodic optical potentials with important contributions of the non-local and anisotropic dipole-dipole interaction, which show a variety of effects such as self-organization and formation of patterns. Here, a macroscopic sample of dipolar bosons in the mean-field limit is addressed. The analysis goes beyond the calculation of ground states and clarifies the role of excited and metastable states in such systems. In particular, the formation of phases is found to originate from the interplay of several states with distinct stability properties. As some of the phases are formed by metastable states, special attention is paid to the characteristics of phase transitions in real time and the dynamical stabilization of the condensate. The dynamical simulations that support these results, constitute a way for an experimental observation of these findings. The third physical application is an open quantum system. Here, an external potential models gain and loss of particles and features parity with simultaneous time-reversal symmetry. For these dipolar condensates real eigenvalues of the nonlinear Hamiltonian are found, preserving the PT-symmetry of the external potential, as well as states that break this symmetry. A detailed stability analysis of these, in general complex states, is performed. The comparison with a similar system featuring a non-dipolar condensate demonstrates the role of the dipolar interaction for novel effects. Furthermore, the real-time dynamics is investigated, which reveals, among other effects, long-living oscillations of the two wells' population.
We derive rigorous one- and two-dimensional mean-field equations for cigar- and pancake-shaped dipolar Bose-Einstein condensates with arbitrary polarization angle. We show how the dipolar interaction modifies the contact interaction of the strongly confined atoms. In addition, our equations introduce a nonlocal potential, which is anisotropic for pancake-shaped condensates. We propose to observe this anisotropy via measurement of the condensate aspect ratio. We also derive analytically approximate density profiles from our equations. Both the numerical solutions of our reduced mean-field equations and the analytical density profiles agree well with numerical solutions of the full Gross-Pitaevskii equation while being more efficient to compute.