Imperfect Construction of Microclusters

Microclusters are the basic building blocks used to construct cluster states capable of supporting fault-tolerant quantum computation. In this paper, we explore the consequences of errors on microcluster construction using two error models. To quantify the effect of the errors we calculate the fidelity of the constructed microclusters and the fidelity with which two such microclusters can be fused together. Such simulations are vital for gauging the capability of an experimental system to achieve fault tolerance.Comment: 5 pages 2 figure

Prostaglandin and Dna Synthesis in Human Skin: Possible Relationship to ultraviolet light effects

The effect of prostaglandin E2 (PGE2) on DNA synthesis in human skin was evaluated. PGE2 (1μg) was injected intradermally into normal buttock skin of 15 volunteers followed by tritiated thymidine for autoradiographic quanitation of DNA sythesizing cells. Controls of normal saline, histamine (50μg), and lower doses of PGE2 were also injected into 8 of the volunteers. Forty-eight hours after injection of 1μg and 0.1μg PGE2 there was a 264% and 62% increase, respectively, in the number of DNA synthesizing epidermal cells/high-power field as compared to saline controls. These differences were statistically significant (p<0.01). Histamine (50μg) produced a statistically significant 36% higher labeling index compared to its saline controls (p<0.05). Many types of skin injury, including ultraviolet light (UVL) irradiation, produce an increase in the number of DNA synthesizing cells about 48 hr after the stimulus. Our findings suggest the PGE, a putative mediator of UVL-induced inflammation, may be one of the chemical mediators for the UVL-induced increase in DNA sythesizing cells. Histamine may also contribute to the increase in DNA synthesizing cells following UVL-induced inflammation

Superoperator Analysis of Entanglement in a Four-Qubit Cluster State

In this paper we utilize superoperator formalism to explore the entanglement evolution of four-qubit cluster states in a number of decohering environments. A four-qubit cluster state is a resource for the performance of an arbitrary single logical qubit rotation via measurement based cluster state quantum computation. We are specifically interested in the relationship between entanglement evolution and the fidelity with which the arbitrary single logical qubit rotation can be implemented in the presence of decoherence as this will have important experimental ramifications. We also note the exhibition of entanglement sudden death (ESD) and ask how severely its onset affects the utilization of the cluster state as a means of implementing an arbitrary single logical qubit rotation.Comment: 9 pages, 9 composite figures, presentation of results completely rewritte