Photon statistics measurement for coherent fields

Olivier Alibart, Djeylan Aktas, Tao Wang +3 more

刘源 刘源, Yuan Liu Yuan Liu, 王俊 王俊 +9 more

An efficient scheme for photon statistics measurement is presented based on the Hanbury-Brown-Twiss configuration. We set the sampling time Ts to satisfy the relationship of TslTdlTm, where Td is the dead time of each detector and Tm is the laser pulse repetition period. And each single photon detector cannot detect more than one photon in each pulse. The approach can sufficiently eliminate the influences of the detector's dead time on photon statistics. At last, the photon statistics of coherent field is experimentally determined.

Ramabhadra Vasudevan

Yujiang Qu, Surendra Singh

Statistical properties of second-harmonic photons generated by a single-mode laser operating near threshold are investigated by means of photoelectric counting measurements. It is found that second-harmonic photons display superthermal fluctuations below threshold where pump statistics are thermal. Above threshold, as the pump field becomes coherent, second-harmonic photons approach Poisson statistics. These measurements, interpreted as two-photon statistics of the fundamental beam, provide experimental evidence for the dependence of the fluctuation properties of a light beam on the process of detection.

Ashfaq H. Khosa, Manzoor Ikram, Muhammad Suhail Zubairy

We propose a scheme for the measurement of joint photon statistics and Wigner function of the entangled field states between two separate cavities. The scheme utilizes the momentum state of the two-level atoms in Bragg's regime. The probability of finding the atom in any one of the momentum states is the product of joint photon statistics and an oscillatory function. The argument of the function contains the information of the joint photon numbers in two cavities. We use the method of state reduction to a single set of joint photon numbers, which is a consequence of the measuring sequence. The repeated measurement of the set of photon numbers gives the joint photon statistics of the entangled field state. The complete entangled state can be reconstructed as a Wigner function from the knowledge of photon statistics of the coherently displaced entangled state.

Edward R. Pike, Eric Jakeman