131 citations · 1.5k across the 69 of their papers we have counts for
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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…
Realization of -symmetric and -symmetry broken states in static optical lattice potentials
Felix Kogel, Sebastian Kotzur, Daniel Dizdarevic +2
R. Labouvie et al. [Phys. Rev. Lett. 116, 235302 (2016)] have described an experiment with a weakly interacting Bose-Einstein condensate trapped in a one-dimensional optical lattic…
Purity oscillations in coupled Bose-Einstein condensates
Jonathan Stysch, Felix Roser, Dennis Dast +2
It is shown that the distinct oscillations of the purity of the single-particle density matrix for many-body open quantum systems with balanced gain and loss reported by Dast et al…
Topological edge states in the Su-Schrieffer-Heeger model subject to balanced particle gain and loss
Marcel Klett, Holger Cartarius, Dennis Dast +2
We investigate the Su-Schrieffer-Heeger model in presence of an injection and removal of particles, introduced via a master equation in Lindblad form. It is shown that the dynamics…
Realization of balanced gain and loss in a time-dependent four-mode Bose-Hubbard model
Daniel Dizdarevic, Jörg Main, Kirill Alpin +4
A quantum system exhibiting symmetry is a Bose-Einstein condensate in a double-well potential with balanced particle gain and loss, which is described in the mean-fi…
PT-symmetric gain and loss in a rotating Bose-Einstein condensate
Daniel Haag, Dennis Dast, Holger Cartarius +1
PT-symmetric quantum mechanics allows finding stationary states in mean-field systems with balanced gain and loss of particles. In this work we apply this method to rotating Bose-E…
Balanced gain and loss in Bose-Einstein condensates without PT symmetry
Philipp Lunt, Daniel Haag, Dennis Dast +2
Balanced gain and loss renders the mean-field description of Bose-Einstein condensates PT symmetric. However, any experimental realization has to deal with unbalancing in the gain…
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…
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…
Bose-Einstein condensates with balanced gain and loss beyond mean-field theory
Dennis Dast, Daniel Haag, Holger Cartarius +2
Most of the work done in the field of Bose-Einstein condensates with balanced gain and loss has been performed in the mean-field approximation using the PT-symmetric Gross-Pitaevsk…
A model of three coupled wave guides and third order exceptional points
W D Heiss, G Wunner
A -symmetric model for three interacting wave guides is investigated. Each wave guide is represented by an attractive -function potential being in equidistant positi…
Rydberg systems in parallel electric and magnetic fields: an improved method for finding exceptional points
Matthias Feldmaier, Jörg Main, Frank Schweiner +2
Exceptional points are special parameter points in spectra of open quantum systems, at which resonance energies degenerate and the associated eigenvectors coalesce. Typical example…
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…
-symmetric currents of a Bose-Einstein condensate in a triple well
Daniel Haag, Dennis Dast, Holger Cartarius +1
We study the case of -symmetric perturbations of Hermitian Hamiltonians with degenerate eigenvalues using the example of a triple-well system. The degeneracy complica…
Purity oscillations in Bose-Einstein condensates with balanced gain and loss
Dennis Dast, Daniel Haag, Holger Cartarius +1
In this work we present a new generic feature of PT-symmetric Bose-Einstein condensates by studying the many-particle description of a two-mode condensate with balanced gain and lo…
Fano resonances in scattering: an alternative perspective
Lukas Schwarz, Holger Cartarius, Günter Wunner +2
In a previous paper it has been shown that the interference of the first and second order pole of the Green's function at an exceptional point, as well as the interference of the f…
Cusp bifurcation in the eigenvalue spectrum of PT-symmetric Bose-Einstein condensates
Daniel Dizdarevic, Dennis Dast, Daniel Haag +3
A Bose-Einstein condensate in a double-well potential features stationary solutions even for attractive contact interaction as long as the particle number and therefore the interac…
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…
Supersymmetric model of a Bose-Einstein condensate in a -symmetric double-delta trap
Nikolas Abt, Holger Cartarius, Günter Wunner
The most important properties of a Bose-Einstein condensate subject to balanced gain and loss can be modelled by a Gross-Pitaevskii equation with an external -symmetr…
Quantum master equation with balanced gain and loss
Dennis Dast, Daniel Haag, Holger Cartarius +1
We present a quantum master equation describing a Bose-Einstein condensate with particle loss on one lattice site and particle gain on the other lattice site whose mean-field limit…
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…
Fano-Feshbach resonances in two-channel scattering around exceptional points
W D Heiss, G Wunner
It is well known that in open quantum systems resonances can coalesce at an exceptional point, where both the energies {\em and} the wave functions coincide. In contrast to the usu…