NameResearch Description
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Ehud Altman

Senior Scientist

Quantum phases of matter are well understood as long as they are perturbatively connected to systems of non interacting particles (Fermions or Bosons) or to states that possess simple order, such as ferromagnets or even antiferromagnets. Dr. Altman is interested in systems, where because of strong interactions, these known paradigms fail and one is forced to search for a different starting point for theoretical investigation...

Quantum phases of matter are well understood as long as they are perturbatively connected to systems of non interacting particles (Fermions or Bosons) or to states that possess simple order, such as ferromagnets or even antiferromagnets. Dr. Altman is interested in systems, where because of strong interactions, these known paradigms fail and one is forced to search for a different starting point for theoretical investigation. This might mean that the system has a simple description only in terms of “particles” or other objects, which are very different from the microscopic constituents (i.e. electrons, ions etc).

Because the route leading from the microscopic Hamiltonian to the appropriate effective description is highly non trivial, striking effects are often not anticipated, and the field continues to produce exciting experimental surprises.

His research in this area includes:

Quantum Magnetism
High Tc superconductivity
Ultra cold atomic gases: Strongly correlated states, Non equilibrium quantum dynamics, Quantum noise

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Peter Zoller

Professor

The research topics of the Zoller group cover the fields of theoretical quantum optics and atomic physics, quantum information, and – since recently – the theory of condensed matter systems. The research is focused on the theoretical description of real physical systems, in close collaboration with the experiment, and the interdisciplinary connection of the stated topics, indicated also by our membership in the SFB “Foundations and Application of Quantum Science” (FoQuS)...

The research topics of the Zoller group cover the fields of theoretical quantum optics and atomic physics, quantum information, and – since recently – the theory of condensed matter systems. The research is focused on the theoretical description of real physical systems, in close collaboration with the experiment, and the interdisciplinary connection of the stated topics, indicated also by our membership in the SFB “Foundations and Application of Quantum Science” (FoQuS). In the field of cold quantum gases especially strongly correlated systems of atoms in optical lattices have been investigated. The variety of the studied systems includes the study of repulsively bound atom pairs, simulations of lattice gauge theories and the proposal for an atomic amplifier (single atom transistor). Further emphasis in the research has been placed on theoretical proposals in the field of cold trapped ions in view of the realization of a scalable quantum computer. In particular new fast quantum gates, mesoscopic ion traps and purely quantum optical aspects, like quantum feedback have been of interest. In the last two years increasing emphasis has been put on the study of dipolar systems. In detail the creation and melting of two dimensional dipolar crystals, a hybrid quantum circuit with dipolar molecules serving as quantum memory coupled to solid state quantum processors, and the implementation of lattice spin models with heteronuclear molecules have been investigated.

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Ignacio Cirac

Director Professor

Our main goals can be summarized as follows. First, we propose and analyze experiments that aim at observing and discovering interesting quantum phenomena in atomic systems. Second, we investigate how atomic systems can be controlled and manipulated at the quantum level using lasers, and how such systems can be scaled up in a controlled way...

Our main goals can be summarized as follows. First, we propose and analyze experiments that aim at observing and discovering interesting quantum phenomena in atomic systems. Second, we investigate how atomic systems can be controlled and manipulated at the quantum level using lasers, and how such systems can be scaled up in a controlled way. Third, we participate in the development of a theory of Quantum Information which will be the basis of the applications in the world of communication and computation once microscopic systems can be completely controlled at the quantum level. Fourth, we apply the ideas and concepts developed in the field of Quantum Optics and Quantum Information to other fields, in particular that of Condensed Matter Physics. Our work is done in strong collaboration with several theoretical and experimental groups inside and outside our Institute, and benefits very much from the visits of many scientists from different institutions around the world.

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David Hunger

Doctor

We developed a method to fabricate micro cavities with optical fibers as mirror substrates. The endfacets of cleaved fibers are laser maschined to obtain a concave surface with ultra low roughness (0.24nm rms). This serves as substrate for HR low loss coatings to provide high finesse mirrors...

We developed a method to fabricate micro cavities with optical fibers as mirror substrates. The endfacets of cleaved fibers are laser maschined to obtain a concave surface with ultra low roughness (0.24nm rms). This serves as substrate for HR low loss coatings to provide high finesse mirrors. Cavities built from pairs of such fibers reached a Finesse of F=38000 with extremely small mode volume V~30µm³. Such cavities can be used for single atom detection and cavity QED experiments on atom chips (pursued in the Group of Prof. Jakob Reichel, LKB/ENS Paris ).

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