131 citations · 818 across the 29 of their papers we have counts for
29 papers
Balancing gain and loss in symmetrised multi-well potentials
Daniel Dizdarevic, Holger Cartarius, Jörg Main +1
Balanced gain and loss leads to stationary dynamics in open systems. This occurs naturally in PT-symmetric systems, where the imaginary part of the potential describing gain and lo…
Stationary states in the many-particle description of Bose-Einstein condensates with balanced gain and loss
Dennis Dast, Daniel Haag, Holger Cartarius +2
Bose-Einstein condensates with balanced gain and loss can support stationary states despite the exchange of particles with the environment. In the mean-field approximation this is…
-symmetric wave guide system with evidence of a third-order exceptional point
Jan Schnabel, Holger Cartarius, Jörg Main +2
An experimental setup of three coupled -symmetric wave guides showing the characteristics of a third-order exceptional point (EP3) has been investigated in an idealiz…
Vortices in Bose-Einstein condensates with -symmetric gain and loss
Lukas Schwarz, Holger Cartarius, Ziad H. Musslimani +2
We investigate vortex excitations in dilute Bose-Einstein condensates in the presence of complex -symmetric potentials. These complex potentials are used to describe…
Relation between -symmetry breaking and topologically nontrivial phases in the SSH and Kitaev models
Marcel Klett, Holger Cartarius, Dennis Dast +2
Non-Hermitian systems with symmetry can possess purely real eigenvalue spectra. In this work two one-dimensional systems with two different topological phases, the t…
Tilted optical lattices with defects as realizations of PT symmetry in Bose-Einstein condensates
Manuel Kreibich, Jörg Main, Holger Cartarius +1
A PT-symmetric Bose-Einstein condensate can theoretically be described using a complex optical potential, however, the experimental realization of such an optical potential describ…
State Flip at Exceptional Points in Atomic Spectra
Henri Menke, Marcel Klett, Holger Cartarius +2
We study the behavior of the non-adiabatic population transfer between resonances at an exceptional point in the spectrum of the hydrogen atom. It is known that, when the exception…
Verification of exceptional points in the collapse dynamics of Bose-Einstein condensates
Jonas Brinker, Jacob Fuchs, Jörg Main +2
In Bose-Einstein condensates with an attractive contact interaction the stable ground state and an unstable excited state emerge in a tangent bifurcation at a critical value of the…
Coupling approach for the realization of a -symmetric potential for a Bose-Einstein condensate in a double well
Fabian Single, Holger Cartarius, Günter Wunner +1
We show how non-Hermitian potentials used to describe probability gain and loss in effective theories of open quantum systems can be achieved by a coupling of the system to an envi…
Realizing PT-symmetric non-Hermiticity with ultra-cold atoms and Hermitian multi-well potentials
Manuel Kreibich, Jörg Main, Holger Cartarius +1
We discuss the possibility of realizing a non-Hermitian, i.e. an open two-well system of ultra-cold atoms by enclosing it with additional time-dependent wells that serve as particl…
Dipolar Bose-Einstein condensates in a PT-symmetric double-well potential
Rüdiger Fortanier, Dennis Dast, Daniel Haag +4
We investigate dipolar Bose-Einstein condensates in a complex external double-well potential that features a combined parity and time-reversal symmetry. On the basis of the Gross-P…
Hermitian four-well potential as a realization of a PT-symmetric system
Manuel Kreibich, Jörg Main, Holger Cartarius +1
A PT-symmetric Bose-Einstein condensate can be theoretically described using a complex optical potential, however, the experimental realization of such an optical potential describ…
A variational approach to Bogoliubov excitations and dynamics of dipolar Bose-Einstein condensates
Manuel Kreibich, Jörg Main, Günter Wunner
We investigate the stability properties and the dynamics of Bose-Einstein condensates with axial symmetry, especially with dipolar long-range interaction, using both simulations on…
A nonlinear dynamics approach to Bogoliubov excitations of Bose-Einstein condensates
M. Kreibich, H. Cartarius, J. Main +1
We assume the macroscopic wave function of a Bose-Einstein condensate as a superposition of Gaussian wave packets, with time-dependent complex width parameters, insert it into the…
Relation between the eigenfrequencies of Bogoliubov excitations of Bose-Einstein condensates and the eigenvalues of the Jacobian in a time-dependent variational approach
Manuel Kreibich, Jörg Main, Günter Wunner
We study the relation between the eigenfrequencies of the Bogoliubov excitations of Bose-Einstein condensates, and the eigenvalues of the Jacobian stability matrix in a variational…
Variational methods with coupled Gaussian functions for Bose-Einstein condensates with long-range interactions. II. Applications
Stefan Rau, Jörg Main, Holger Cartarius +2
Bose-Einstein condensates with an attractive 1/r interaction and with dipole-dipole interaction are investigated in the framework of the Gaussian variational ansatz introduced by S…
Variational methods with coupled Gaussian functions for Bose-Einstein condensates with long-range interactions. I. General concept
Stefan Rau, Jörg Main, Günter Wunner
The variational method of coupled Gaussian functions is applied to Bose-Einstein condensates with long-range interactions. The time-dependence of the condensate is described by dyn…
Pitchfork bifurcations in blood-cell shaped dipolar Bose-Einstein condensates
Stefan Rau, Jörg Main, Patrick Köberle +1
We demonstrate that the method of coupled Gaussian wave packets is a full-fledged alternative to direct numerical solutions of the Gross-Pitaevskii equation of condensates with ele…
Nonlinear Dynamics of Bose-Einstein Condensates with Long-Range Interactions
G. Wunner, H. Cartarius, T. Fabčič +3
The motto of this paper is: Let's face Bose-Einstein condensation through nonlinear dynamics. We do this by choosing variational forms of the condensate wave functions (of given sy…
Discovery of exceptional points in the Bose-Einstein condensation of gases with attractive 1/r-interaction
Holger Cartarius, Jörg Main, Günter Wunner
The extended Gross-Pitaevskii equation for the Bose-Einstein condensation of gases with attractive 1/r-interaction has a second solution which is born together with the ground stat…
Superiority of semiclassical over quantum mechanical calculations for a three-dimensional system
J. Main, G. Wunner, E. Atilgan +2
In systems with few degrees of freedom modern quantum calculations are, in general, numerically more efficient than semiclassical methods. However, this situation can be reversed w…
Periodic orbit quantization of chaotic maps by harmonic inversion
K. Weibert, J. Main, G. Wunner
A method for the semiclassical quantization of chaotic maps is proposed, which is based on harmonic inversion. The power of the technique is demonstrated for the baker's map as a p…
Use of Harmonic Inversion Techniques in the Periodic Orbit Quantization of Integrable Systems
K. Weibert, J. Main, G. Wunner
Harmonic inversion has already been proven to be a powerful tool for the analysis of quantum spectra and the periodic orbit orbit quantization of chaotic systems. The harmonic inve…
Comment on "Recurrences without closed orbits"
J. Main
In a recent paper Robicheaux and Shaw [Phys. Rev. A 58, 1043 (1998)] calculate the recurrence spectra of atoms in electric fields with non-vanishing angular momentum <L_z> not equa…