Conditional quantum state engineering in repeated 2-photon down conversion

The U(1,1) and U(2) transformations realized by three-mode interaction in the respective parametric approximations are studied in conditional measurement, and the corresponding non-unitary transformation operators are derived. As an application, the preparation of single-mode quantum states using an optical feedback loop is discussed, with special emphasis of Fock state preparation. For that example, the influence of non-perfect detection and feedback is also considered.Comment: 17 pages, 4 figures, using a4.st

Stratigraphy and Structure of the Miocene Esmeralda Formation in Stewart Valley, Mineral County, Nevada

The Miocene rocks of Stewart Valley, eastern Mineral County, Nevada, consist of volcanic flows and breccias and fluvio-lacustrine sedimentary rocks. They are called the Esmeralda Formation because they contain lithologies similar to those of the Esmeralda type section 100km south; however, the rocks in Stewart Valley were probably deposited in a separate local basin. The lower part of this formation contains small lacustrine claystone deposits (unit 1) that interfinger with volcanic breccias and flows (unit 2). The main fluvio-lacustrine sequence is above the flows and·is divided by the author into five units based on lithology: sandstone and claystone in unit 3, shale in unit 4, claystone and mudstone in unit 5, sandstone and carbonate in unit 6, and sandstone and vitric tuff in unit 7. The total thickness of the formation is about 600m. Younger basalt flows lie unconformably above the Esmeralda Formation in part of the Gabbs Valley Range. Plio-Pleistocene conglomerates and pediment gravels overlie with angular unconformity the Esmeralda Formation in the valley. During the early Miocene, Stewart Valley was downdropped as a graben. On the east side of the valley the Cedar Mountains were uplifted, but not to their present height. On the west side of the valley the Gabbs Valley Range was uplifted along the Battle\u27s Well Fault. However, this fault is mainly a strike-slip fault associated with Walker Lane and most of the displacement on the fault was horizontal. During most of the Miocene the valley was tectonically stable and the main drainage was south. The lake that formed in the valley fluctuated in size and depth, at times connecting with basins to the south and east. In this lake the sediments of the Esmeralda Formation were deposited. At the end of the Miocene, more faulting occurred on the east and southeast sides of the valley and sub-parallel to the valley axis, altering drainage to the north. These faults cut the Miocene fluvio-lacustrine rocks, but not the later Plio-Pleistocene sediments. The upthrown side of these dip-slip faults is usually on the east side, toward the Cedar Mountains. This fault pattern, along with the general eastward dip of the sediments and the steep gravity gradient near the Cedar Mountains, suggests tilted block faulting. The Gabbs Valley Range-Stewart Valley block was tilted east and was dropped relative to the Cedar Mountain block

SAMPLING OF SOILS WITH METALLIC RESIDUES COLLECTED FROM MILITARY SMALL-ARMS RANGES

Small-arms, artillery, mortar, and pyrotechnic military training introduces solid metallic residues into the environment. Previous energetic residue research showed conventional judgmental soil sampling and associated sample preparation methodologies are inadequate to address the heterogeneous distribution and still yield representative and reproducible results for the area of interest. Metallic residue deposition at military small-arms ranges occurs in a heterogeneous distributional pattern, similar to solid particulate energetic residue deposition. One of the primary objectives of an environmental investigation is to estimate the mean contaminant concentration to evaluate human and ecological risk in an exposure unit (i.e., an area where the receptors are exposed to contamination). One assumption of the risk assessment is that the receptors spend an equal amount of time in every portion of the exposure unit. Evaluation of the appropriateness of conventional soil sampling for military small-arms ranges with solid metallic residues indicated the conventional approach of judgmental sampling was inadequate for providing representative and reproducible mean estimates for the exposure unit. Consequently, a series of experiments evaluated possible changes to the field sampling and laboratory sample preparation procedures to improve the representativeness and reproducibility of the sample results. The outcome of this study found that a collective series of changes involving soil sampling and sample preparation procedures provided superior estimates of the population (exposure unit) relative to conventional grab sampling. Overall, the dissertation results indicate a sampling approach referred to as the Incremental Sampling Methodology (ISM) provided an improved estimate of the population (exposure unit) relative to conventional grab sampling and has the potential to reduce sampling costs by 5 to 50 percent. Incorporation of the dissertation findings into suggested modifications for United States Environmental Protection Agency SW-846 Method 3050B for digestion of soils or sediments undergoing metals analysis is in progress; including the addition of an appendix outlining the procedures for collection of systematic random surface soil samples in the field using the incremental approach

Study of a heat rejection system using capillary pumping

Results of an analytical study investigating the application of capillary pumping to the heat rejection loop of an advanced Rankine cycle power conversion system are presented. The feasibility of the concept of capillary pumping as an alternate to electromagnetic pumping is analytically demonstrated. Capillary pumping is shown to provide a potential for weight and electrical power saving and reliability through the use of redundant systems. A screen wick pump design with arterial feed lines was analytically developed. Advantages of this design are high thermodynamic and hydrodynamic efficiency, which provide a lightweight easily packaged system. Operational problems were identified which must be solved for successful application of capillary pumping. The most important are the development of start up and shutdown procedures, and development of a means of keeping noncondensibles from the system and of earth-bound testing procedures

Tun formation is not a prerequisite for desiccation tolerance in the marine tidal tardigrade Echiniscoides sigismundi

The so-called ‘tun’ state is best known from limno-terrestrial tardigrades and rotifers that rely on this compact body shape for anhydrobiotic survival. Little is known of tun formation in marine species and the evolutionary origin of the state is presently unknown. Here, we investigate desiccation tolerance and tun formation in the marine tidal echiniscoidean tardigrade, Echiniscoides sigismundi (M. Schultze, 1865). Groups of approximately 20 E. sigismundi sampled from Lynæs (Denmark) were dehydrated on filter paper from seawater as well as ultrapurified water and kept for 48 h at 5 °C, after which they were rehydrated in seawater. The activity and behaviour of the tardigrades was examined under a light microscope, whereas scanning electron microscopy was used for high-resolution three-dimensional imaging. When dehydrated from seawater, E. sigismundi enters a tun, however, when exposed to ultrapurified water, the tardigrade swells and becomes incapable of movement, and thus incapable of tun formation. Nonetheless, E. sigismundi tolerates being dehydrated from ultrapurified water, revealing an exceptional and unparalleled resilience towards losing structural integrity. Our results confirm previous investigations, which suggest that tun formation relies on a functional musculature. They further suggest that tun formation may have evolved as a response to elevated external pressure rather than desiccation per se

Quantum state conversion by cross-Kerr interaction

A generalized Mach-Zehnder-type interferometer equipped with cross-Kerr elements is proposed to convert N-photon truncated single-mode quantum states into (N+1)-mode single-photon states, which are suitable for further state manipulation by means of beam splitter arrays and ON/OFF-detections, and vice versa. Applications to the realization of unitary and non-unitary transformations, quantum state reconstruction, and quantum telemanipulation are studied.Comment: 22 pages, 4 figures, using a4.st

Entanglement purification of multi-mode quantum states

An iterative random procedure is considered allowing an entanglement purification of a class of multi-mode quantum states. In certain cases, a complete purification may be achieved using only a single signal state preparation. A physical implementation based on beam splitter arrays and non-linear elements is suggested. The influence of loss is analyzed in the example of a purification of entangled N-mode coherent states.Comment: 6 pages, 3 eps-figures, using revtex