News

Tue January 1, 2013

Timekeeping with Electronic Spin States in Diamond

Frequency standards based on atomic states, such as Rb or Cs vapors, or single-trapped ions, are the most precise measures of time. We proposed and analyzed a precision oscillator approach based upon spins in a solid-state system, in particular, the nitrogen-vacancy defect in single-crystal diamond. We showed that that system could have stability that approached...
Read More »
News type:
Research Highlights
Tue January 1, 2013

All-Optical Switch and Transistor Gated by One Stored Photon

In this paper we demonstrate an all-optical switch gated by one stored photon. Using an atomic ensemble trapped inside an optical cavity, we store a photon incident transverse to the cavity in the atomic ensemble, thereby changing the state of one atom. This atom then blocks the cavity for photons incident along the cavity axis....
Read More »
News type:
Research Highlights
Tue January 1, 2013

Many-body Localization with Dipoles

Systems of strongly interacting dipoles offer an attractive platform to study many-body localized phases, owing to their long coherence times and strong interactions. We explored conditions under which such localized phases persisted in the presence of power-law interactions and supplemented our analytic treatment with numerical evidence of localized states in one dimension. We proposed several...
Read More »
News type:
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...
Read More »
News type:
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...
Read More »
News type:
Research Highlights
Tue January 1, 2013

Single-photon Nonlinearities in Two-mode Optomechanics

We presented a detailed theoretical analysis of a weakly driven, multimode optomechanical system, in which two optical modes were strongly and near-resonantly coupled to a single mechanical mode via a three-wave mixing interaction. We calculated one- and two-time intensity correlations of the two optical fields and compared them to analogous correlations in atom-cavity systems. Nonclassical...
Read More »
News type:
Research Highlights
Tue January 1, 2013

Progress on Laser Cooling of CaF

The internal structure and the long-range dipole-dipole interactions of ultracold polar molecules open new avenues in studying physics such as the quantum simulation of strongly correlated Hamiltonians, ultracold controlled chemistry or precision measurements. At present, a reliable general method to produce an ultracold sample of molecules is desired, but not available. The goal of this...
Read More »
News type:
Research Highlights
Tue January 1, 2013

A Quantum Network of Clocks

The development of precise atomic clocks has led to many scientific and technological advances that play an increasingly important role in modern society. Shared timing information constitutes a key resource for positioning and navigation with a direct correspondence between timing accuracy and precision in applications such as the Global Positioning System (GPS). By combining precision...
Read More »
News type:
Research Highlights
Tue January 1, 2013

Phonon-induced Spin-Spin Interactions in Diamond Nanostructures: Application to Spin Squeezing

We proposed and analyzed a novel mechanism for long-range spin-spin interactions in diamond nanostructures. The interactions between electronic spins, associated with nitrogen-vacancy centers in diamond, were mediated by their coupling via strain to the vibrational mode of a diamond mechanical nanoresonator. That coupling resulted in phonon-mediated effective spin-spin interactions that could be used to generate...
Read More »
News type:
Research Highlights
Tue January 1, 2013

Keldysh Approach for Non-equilibrium Phase Transitions in Quantum Optics: Beyond the Dicke Model in Optical Cavities

We investigated nonequilibrium phase transitions for driven atomic ensembles interacting with a cavity mode and coupled to a Markovian dissipative bath. In the thermodynamic limit and at low frequencies, we showed that the distribution function of the photonic mode was thermal, with an effective temperature set by the atom-photon interaction strength. That behavior characterized the...
Read More »
News type:
Research Highlights