Generation of entangled states of two atoms inside a leaky cavity

An in-depth theoretical study is carried out to examine the quasi-deterministic entanglement of two atoms inside a leaky cavity. Two $\Lambda$-type three-level atoms, initially in their ground states, may become maximally entangled through the interaction with a single photon. By working out an exact analytic solution, we show that the probability of success depends crucially on the spectral function of the injected photon. With a cavity photon, one can generate a maximally entangled state with a certain probability that is always less than 50%. However, for an injected photon with a narrower spectral width, this probability can be significantly increased. In particular, we discover situations in which entanglement can be achieved in a single trial with an almost unit probability

A high-throughput overlay multicast infrastructure with network coding

Network coding has been recently proposed in information theory as a new dimension of the information multicast problem that helps achieve optimal transmission rate or cost. End hosts in overlay networks are natural candidates to perform network coding, due to its available computational capabilities. In this paper, we seek to bring theoretical advances in network coding to the practice of high-throughput multicast in overlay networks. We have completed the first real implementation of network coding in end hosts, as well as decentralized algorithms to construct the routing strategies and to perform random code assignment. Our experiences suggest that approaching maximum throughput with network coding is not only theoretically sound, but also practically promising. We also present a number of unique challenges in designing and realizing coded data dissemination, and corresponding solution techniques to address them

Providing Efficient I/O Redundancy in MPI Environments

Highly parallel applications often make use of either highly parallel file systems or large numbers of independent disks. Either of these approaches can provide high data rates necessary for parallel applications. However, the failure of a single link..