News: Research Highlights

Fri January 1, 2010

Probing quantum phase transitions at the single-atom level

Physicists Get an Up–Close Look at Synthetic Quantum Materials

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Fri January 1, 2010

Thermometry and Refrigeration in a Two-Component Mott Insulator of Ultracold Atoms

In this work [1], we describe and analyze theoretically the two techniques of spin-gradient thermometry and spin gradient demagnetization cooling developed earlier by our group [2, 3].
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Thu January 1, 2009

Near Field Electrical Detection of Optical Plasmons and Single Plasmon Sources

A. Falk, F. L. Koppens, C. L. Yu, K. Kang, N. d. L. Snapp, A. V. Akimov, M. Jo, M. D. Lukin, and H. Park, Near Field Electrical Detection of Optical Plasmons and Single Plasmon Sources, Nature Physics 5, 475-479 doi:10.1038/nphys1284 (2009).
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Thu January 1, 2009

Observartion of itinerant ferromagnetism in a strongly interacting Fermi gas of ultracold atoms

Ferromagnetism of delocalized (itinerant) fermions occurs due to repulsive interactions and the exchange energy which reduces the interaction energy for spin polarized domains due to the Pauli exclusion principle.  At a critical interaction, given by the so-called Stoner criterion [1], they system spontaneously develops domains and becomes ferromagnetic.  This, together with a suitable band structure...
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Thu January 1, 2009

Buffer-gas Cooled Bose-Einstein Condensate

Now well into its second decade, the experimental realization of Bose-Einstein condensation (BEC) in dilute gases has led to revolutionary advances in physics. Since this achievement the field has moved quickly, with innumerable new developments in coherent atom and molecular optics and nonlinear atom optics, the observation of superfluidity in atomic gases, the study of novel quantum systems, and most recently the study of the BEC-BCS crossover. Despite the breadth of new research, however, the basic recipe for BEC is unchanged from its first realization in alkali atoms: pre-cool a hot sample utilizing laser cooling to permit trapping and provide high densities, followed by evaporative cooling to reach quantum degeneracy.

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Thu January 1, 2009

A quantum gas microscope for detecting single atoms in a Hubbard-regime optical lattice

For the first time it was possible to observe single atoms in an optical lattice, where particles can tunnel from site to site.  An optical lattice is a crystals made of light that can be used to trap atoms at very low temperatures, creating a test bed for fundamental properties of crystalline materials. This research is part of a program on studying novel quantum matter using ultracold quantum gases. The work is led by Markus Greiner, Assistant Professor of Physics, principal investigator at Harvard and member at the NSF funded Harvard-MIT “Center for Ultracold Atoms”.

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Thu January 1, 2009

Demonstration of resolved sideband cavity cooling of a single ion

This is joint work with Vladan Vuletic.
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Thu January 1, 2009

Intense Atomic and Molecular Beams via Neon Buffer gas Cooling

D. Patterson, J. Rasmussen and J.M. Doyle, New Journal of Physics submitted (2009)
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