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Doerte Blume

Publications and source records attributed to Doerte Blume.

4 recordsLinked to original sources

Engineering Dynamical Phase Diagrams with Driven Lattices in Spinor Gases

We experimentally demonstrate that well-designed driven lattices are versatile tools to simultaneously tune multiple key parameters (namely spin-dependent interactions, spinor phase, and Zeeman energy) for manipulating phase diagrams of spinor gases with negligible heating and atom losses. This opens a new avenue for studying dynamical phase transitions in engineered Hamiltonians. The driven lattice creates additional separatrices in phase space at driving-frequency-determined locations, with progressively narrower separatrices at higher Zeeman energies due to modulation-induced higher harmonics. The vastly expanded range of magnetic fields at which significant spin dynamics occur and improved sensitivities at higher harmonics represent a step towards quantum sensing with ultracold gases.

cond-mat.quant-gas

Manipulation of nonequilibrium spin dynamics of an ultracold gas in a moving optical lattice

The isolation and control of disparate degrees of freedom underpin quantum simulators. We advance the programmability of cold atom quantum simulators with a first realization of the dynamic interplay of spatial and spin degrees of freedom. We experimentally demonstrate that violent spatial evolutions tune long-lived coherent spin dynamics and develop a model of quantum spin-mixing incorporating the spatial evolution via time-dependent spin-spin interactions. Our results open new paths towards the simulation of quantum spin models with tunable interactions via tailored spatial dynamics.

cond-mat.quant-gas

Energetics and structural properties of two- and three-boson systems in the presence of 1D spin-orbit coupling

It was shown recently that the discrete scaling symmetry, which underlies the Efimov effect in the three identical boson system with two-body short-range interactions, survives when single-particle 1D spin-orbit coupling terms are added to the Hamiltonian. Each three-body energy level in the ordinary Efimov scenario turns into an energy manifold that contains four energy levels in the presence of 1D spin-orbit coupling (equal mixture of Rashba-Dresselhaus coupling). This work provides a detailed characterization of the energy levels in these manifolds. The two-boson energies, which enter into the three-boson scattering threshold, are analyzed in detail. Moreover, the structural properties, e.g., momentum distributions of the two- and three-boson systems, are analyzed for various parameter combinations.

cond-mat.quant-gas

Electric-field induced helium-helium resonances

The tunability of the helium-helium interaction through an external electric field is investigated. For a static external field, electric-field induced resonances and associated electric-field induced bound states are calculated for the $^4$He-$^4$He, $^3$He-$^4$He, and $^3$He-$^3$He systems. Qualitative agreement is found with the literature for the $^3$He-$^4$He and $^3$He-$^3$He systems [E. Nielsen, D. V. Fedorov, and A. S. Jensen, Phys. Rev. Lett. {\bf{82}}, 2844 (1999)]. The implications of the predicted electric-field induced resonances for $^4$He-$^4$He on the wave packet dynamics, initiated by intense laser pulses, are investigated. Our results are expected to guide next generation experiments.

cond-mat.quant-gas