Ni Ni, University of California, Los Angeles
Quantized vibrations of the lattice (phonons) are intrinsic to all of condensed- matter physics. Most experimental probes, however, treat the phonons in terms of thermal-equilibrium quantities such as heat capacity and thermal conductance, rather than directly addressing the vibrational quanta. I will discuss two types of experiments employing nanofabricated devices and low-temperature techniques to explore and exploit non-equilibrium phonon behavior.
A fundamental question in complexity theory is how much resource is
needed to solve k independent instances of a problem compared to the
resource required to solve one instance. Suppose solving one instance of
a problem with probability of correctness p, we require c units of some
resource in a given model of computation. A direct sum theorem states
that in order to compute k independent instances of a problem, it
1) How to experimentally test the notion of noncontextuality
Rob Spekkens
2) How to demonstrate contextuality in a realistic experiment
Matthew Pusey
The advantages of single photons make them not only the workhorse of testing the foundations of quantum physics against the classical interpretation of nature, but also suitable for various tasks in quantum information processing. In my talk, I will first present our long-distance quantum teleportation with active feed-forward in real time. This experiment uses both quantum and classical optical links over 143 km free space between the two Canary Islands of La Palma and Tenerife and is a major step towards quantum communication on a global scale.
Localizing arrays of atoms in photonic crystals could provide new capabilities for quantum networks and quantum many-body physics. Intriguing theoretical analyses suggest the emergence of completely new paradigms for strong atom-photon interactions that exploit the tremendous flexibility for modal and dispersion engineering of one and two-dimensional photonic crystals.
In the XENON dark matter search experiment, trace contamination of Xe by Kr contributes background events through the beta decay of radioactive Kr-85. To achieve the required sensitivity of the detector, the contamination must be reduced below the part per trillion (ppt) level and this level must be known precisely. We have developed an atom trap trace analysis (ATTA) device using standard atom cooling and trapping techniques to detect Kr below the ppt level.
The coupling between light and a single atom is probably the most fundamental process in quantum optics. The best strategy for efficiently coupling light to a single atom in free space depends on the goal. If the goal is to maximally attenuate a laser beam, narrow-band on- resonance laser radiation is required as well as a wave front approaching the atom from a 2_ solid angle.
I will introduce the field of quantum simulations from a wide
scientific perspective. Then, I will discuss the relevance of quantum
simulations for reproducing different aspects of quantum physics:
nonrelativistic and relativistic quantum dynamics, physical and unphysical
quantum operations, as well as strong and ultrastrong light-matter
interactions. Finally, I will give examples in the context of trapped-ion
and circuit QED technologies.
Nanophotonic devices allow for realizing complex optical functionality that is otherwise difficult to achieve with free-space optical setups. While such circuits find a multitude of applications in telecommunication and optical signal processing, their tremendous potential for non-classical optics remains largely unexplored. I will present an integrated platform in which key challenges of integrated quantum optics are addressed by combining nanophotonic and superconducting nanowire devices with optomechanical resonators.