2,737 research outputs found
Intermodal entanglement in Raman processes
The operator solution of a completely quantum mechanical Hamiltonian of the
Raman processes is used here to investigate the possibility of obtaining
intermodal entanglement between different modes involved in the Raman processes
(e.g. pump mode, Stokes mode, vibration (phonon) mode and anti-Stokes mode).
Intermodal entanglement is reported between a) pump mode and anti-Stokes mode,
b) pump mode and vibration (phonon) mode c) Stokes mode and vibration phonon
mode, d) Stokes mode and anti-stokes mode in the stimulated Raman processes for
the variation of the phase angle of complex eigenvalue of pump
mode . Some incidents of intermodal entanglement in the spontaneous and the
partially spontaneous Raman processes are also reported. Further it is shown
that the specific choice of coupling constants may produce genuine entanglement
among Stokes mode, anti-Stokes mode and vibration-phonon mode. It is also shown
that the two mode entanglement not identified by Duan's criterion may be
identified by Hillery-Zubairy criteria. It is further shown that intermodal
entanglement, intermodal antibunching and intermodal squeezing are independent
phenomena.Comment: 11 pages, 4 figure
Hydraulic fracture at the dam-foundation interface using the scaled boundary finite element method coupled with the cohesive crack model
The scaled boundary finite element method coupled with the cohesive crack model is extended to investigate the hydraulic fracture at the dam-foundation interface. The concrete and rock bulk are modeled by the scaled boundary polygons. Cohesive interface elements model the fracture process zone between the crack faces. The cohesive tractions are modeled as side-face tractions in the scaled boundary polygons. The solution of the stress field around the crack tip is expressed semi-analytically as a power series. Accurate displacement field, stress field and stress intensity factors can be obtained without asymptotic enrichment or local mesh refinement. The proposed procedure is verified by the hydraulic fracture of a rectangular embankment on rigid foundation and applied to the modeling of hydraulic fracture on the dam-foundation interface of a benchmark dam. Different distributions of water pressure inside the crack are investigated. It is found that the water pressure inside the crack decreases the peak overflow to less than 20% of the case without water in the crack. Considering the water lag or not is significant to the response, while different distribution of pressure following the water lag region in the fracture process zone has negligible influence
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