Entanglement Degree Characterization of Spontaneous Parametric-Down Conversion Biphotons in Frequency Domain
نویسندگان
چکیده
We present an experiment addressed to verify the validity of the entanglement quantifier R, defined as the ratio between single counts and coincidence distribution width for pure biphoton states generated by short pump pulses. We demonstrate that this ratio can be efficient to estimate entanglement degree in frequency domain. Our work has been performed with a femto second pulsed laser pump addressed to a LiIO3 crystal generating correlated biphotons through collinear degenerate type-I SPDC. To study the dependence of R on the length of the crystal we performed two sequence of measurements for each crystal firstly with a 10 mm and then with a 5 mm.
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