Robustness of noise-present Bell's inequality violation by entangled   state
  The robustness of Bell's inequality (in CHSH form) violation by entangled state in the simultaneous presence of colored and white noise in the system is considered. A twophoton polarization state is modeled by twoparameter density matrix. Setting parameter values one can vary the relative fraction of pure entangled Bell's state as well as white and colored noise fractions. Bell's operator-parameter dependence analysis is made. Computational results are compared with experimental data [quant-ph/0511265] and with results computed using a oneparameter density matrix [doi: 10.1103/PhysRevA.72.052112], which one can get as a special case of the model considered in this work. 
Ivan S. Dotsenko (1), Volodymyr G. Voronov (1) ((1) Faculty of   Physics, Taras Shevchenko Kyiv National University, Ukraine)