News: Research Highlights

Tue January 1, 2013

Stretchable Photonic Crystal Cavity with Wide Frequency Tunability

We reported a new approach for the realization of a flexible photonic crystal (PC) cavity that enabled wide-range tuning of its resonance frequency. Our PC cavity consisted of a regular array of silicon nanowires embedded in a polydimethylsiloxane (PDMS) matrix and exhibited a cavity resonance in the telecommunication band that could be reversibly tuned over...
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Research Highlights
Tue January 1, 2013

Probing Real-space and Time Resolved Correlation Functions with Many-body Ramsey Interferometry

We proposed to use Ramsey interferometry and single-site addressability, available in synthetic matter such as cold atoms or trapped ions, to measure real-space and time-resolved spin correlation functions. Those correlation functions directly probed the excitations of the system, which made it possible to characterize the underlying many-body states. Moreover, they contained valuable information about phase...
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Research Highlights
Tue January 1, 2013

Non-Equilibrium Fractional Quantum Hall State of Light

We investigated the quantum dynamics of systems, which involved small numbers of strongly interacting photons. Specifically, we developed an efficient method to investigate such systems when they were externally driven with a coherent field. Furthermore, we showed how to quantify the many-body quantum state of light via correlation functions. Finally, we applied that method to...
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Research Highlights
Tue January 1, 2013

Enhanced Anti-ferromagnetic Exchange between Magnetic Impurities in a Superconducting Host

It is generally believed that superconductivity only weakly affects the indirect exchange between magnetic impurities. If the distance r between impurities is smaller than the superconducting coherence length (), this exchange is thought to be dominated by RKKY interactions, identical to those in a normal metallic host. This perception is based on a perturbative treatment...
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Research Highlights
Tue January 1, 2013

Beyond Universal Long-Range van der Waals Interactions with Ultracold 6Li2 Molecules

We have found that collisional loss of ultracold 6Li2 molecules can be determined by physics beyond universal long-range van der Waals interactions [1]. Starting with a degenerate Fermi gas of 6Li produced by sympathetic cooling with bosonic 23Na, we form Li2 molecules by a magnetic field sweep around a narrow Feshbach resonance. The resulting molecules...
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Research Highlights
Tue January 1, 2013

Unconventional Magnetism via Optical Pumping of Interacting Spin Systems

We considered strongly interacting systems of effective spins, subject to dissipative spin-flip processes associated with optical pumping. We predicted the existence of novel magnetic phases in the steady state of that system, which emerged due to the competition between coherent and dissipative processes. Specifically, for strongly anisotropic spin-spin interactions, we found ferromagnetic, antiferromagnetic, spin-densitywave, and...
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Research Highlights
Tue January 1, 2013

Spin-Orbit Suppression of Cold Inelastic Collisions of Aluminum and Helium

Cold collisions between atoms play a critical role in much of atomic physics, being responsible for few-body interactions, thermalization, trap loss and decoherence.  The development of a detailed understanding of collisions is therefore crucial to the continued expansion of the field into new atomic systems, an expansion that has already led to the discovery of...
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Research Highlights
Sun January 1, 2012

Vacuum-Induced Transparency

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Research Highlights
Sun January 1, 2012

Initialization and readout of spin chains for quantum information transport

In these works we studied theoretically and experimentally the many-body dynamics of spin systems and analyzed conditions that would allow for their use in quantum communication.
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Research Highlights
Sun January 1, 2012

Compressibility of an ultracold Fermi gas with repulsive interactions

To study the effect of repulsive interactions on the equation of state of a Fermi we have measured the isothermal compressibility of the gas as a function of interaction strength [1].  The strength of repulsive interactions for 6Li atoms can be arbitrarily tuned by varying the magnetic field around a broad Feshbach resonance centered at...
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News type:
Research Highlights