Balance of Polarization in a Hybrid Fiber Optic Sensor

This paper presents the eect of light polarization in a hybrid ber optic sensor. The hybrid sensor is dened as a combination of interferometer sensor and modalmetric sensor. Hybrid sensor system is based on the eect of outputting interferometric sensor of interference as a result of changes made by the modalmetric system. Balance of polarization in the arms of classical interferometer sensor leads to improvement of contrast of interference pattern at the output of the interferometer. Aim of this study is to present a balance light polarization eects in a hybrid system

Statistical properties of random density matrices

Statistical properties of ensembles of random density matrices are investigated. We compute traces and von Neumann entropies averaged over ensembles of random density matrices distributed according to the Bures measure. The eigenvalues of the random density matrices are analyzed: we derive the eigenvalue distribution for the Bures ensemble which is shown to be broader then the quarter--circle distribution characteristic of the Hilbert--Schmidt ensemble. For measures induced by partial tracing over the environment we compute exactly the two-point eigenvalue correlation function.Comment: 8 revtex pages with one eps file included, ver. 2 - minor misprints correcte

Negativity of the Wigner function as an indicator of nonclassicality

A measure of nonclassicality of quantum states based on the volume of the negative part of the Wigner function is proposed. We analyze this quantity for Fock states, squeezed displaced Fock states and cat-like states defined as coherent superposition of two Gaussian wave packets.Comment: 10 pages, 7 figure