4,909 research outputs found
Spin Dependence of Interfacial Reflection Phase Shift at Cu/Co Interface
The spin dependent reflection at the interface is the key element to
understand the spin transport. By completely solving the scattering problem
based on first principles method, we obtained the spin resolved reflectivity
spectra. The comparison of our theoretical results with experiment is good in a
large energy scale from Fermi level to energy above vacuum level. It is found
that interfacial distortion is crucial for understanding the spin dependence of
the phase gain at the CuCo interface. Near the Fermi level, image state
plays an important role to the phase accumulation in the copper film.Comment: 6 papges, 3 figures, accepted by Physical Review
Cavity optomechanical coupling assisted by an atomic gas
We theoretically study a cavity filled with atoms, which provides the
optical-mechanical interaction between the modified cavity photonic field and a
movable mirror at one end. We show that the cavity field ``dresses'' these
atoms, producing two types of polaritons, effectively enhancing the radiation
pressure of the cavity field upon the end mirror, as well as establishing an
additional squeezing mode of the end mirror. This squeezing produces an
adiabatic entanglement, which is absent in usual vacuum cavities, between the
oscillating mirror and the rest of the system. We analyze the entanglement and
quantify it using the Loschmidt echo and fidelity.Comment: 8 pages, 4 figure
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