Wed, January 1, 2014

Scattering Resonances and Bound States for Strongly Interacting Rydberg Polaritons

We provided a theoretical framework, which described slow-light polaritons interacting via atomic Rydberg states. We used a diagrammatic method to analytically derive the scattering properties of two polaritons. We identified new parameter regimes where polariton-polariton interactions were repulsive. Furthermore, in the regime of attractive interactions, we identified multiple two-polariton bound states, calculated their dispersion, and...

Wed, January 1, 2014

Interferometric Probes of Many-body Localization

We proposed a method for detecting many-body localization (MBL) in disordered spin systems. The method involved pulsed, coherent spin manipulations that probed the dephasing of a given spin due to its entanglement with a set of distant spins. It allowed one to distinguish the MBL phase from a non-interacting localized phase and a delocalized phase....

Wed, January 1, 2014

Many-body Dynamics of Dipolar Molecules in an Optical Lattice

Understanding the many-body dynamics of isolated quantum systems is one of the central challenges in modern physics. To this end, the direct experimental realization of strongly correlated quantum systems allows one to gain insights into the emergence of complex phenomena. Such insights enable the development of theoretical tools that broaden our understanding. In our study,...

Wed, January 1, 2014

Properties of the ground 3F2 state and the excited 3P0 state of atomic thorium in cold collisions with 3He

We measure inelastic collisional cross sections for collisions between thorium (Th) and helium. We determine for Th 3F2-He the ratio of the momentum-transfer to Zeeman relaxation cross sections for collisions to be g~500 at 800 mK. For Th 3P0-He collisions, we observe no measureable quenching of this metastable state, even after 106 collisions. This allowed...

Wed, January 1, 2014

Time-resolved magnetic sensing with electronic spins in diamond

One of the most promising applications of quantum information is in precision metrology. In the past year we focused on magnetic sensing with NV centers in diamond, in particular focusing on techniques to extend magnetic field sensing at the nano-scale to time-dependent reconstruction of magnetic fields and spectroscopy.

Wed, January 1, 2014

Coherent Optical Transitions in Implanted Nitrogen-vacancy Centers

Wed, January 1, 2014

Quantum Interference Between Independent Reservoirs in Open Quantum Systems

When a quantum system interacts with multiple reservoirs, the environmental effects are usually treated in an additive manner. We showed that that assumption breaks down for non-Markovian environments that have finite memory times. Specifically, we demonstrated that quantum interferences between independent environments could qualitatively modify the dynamics of the physical system. We illustrated that effect...

Wed, January 1, 2014

Buffer-gas loaded magneto-optical traps for Yb, Tm, Er, and Ho

Novel physics in areas like quantum information, cold controlled chemistry and precision measurements is predicted to be accessible with molecules at temperatures in the mK regime. These approaches require molecular beam sources which are unavailable at present. In particular, providing cold, slow and bright beams of a general set of molecules, ideally independent of their...

Tue, January 1, 2013

Collectively Enhanced Interactions in Solid-state Spin Qubits

We proposed and analyzed a technique to collectively enhance interactions between solid-state quantum registers composed from random networks of spin qubits. In such systems, disordered dipolar interactions generically result in localization. In our study, we demonstrated the emergence of a single collective delocalized eigenmode as one turned on a transverse field. The interaction strength between...

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...