Event Details

Hanbury-Brown-Twiss effect is a prominent 2nd-order inference in the intensities received by two detectors from a beam of particles. The experiments had been extensively performed in various systems including cosmic rays, neutrons and photons. HBT effect can be generally attributed to the wave-particle duality of the beams, which however, becomes less intuitive in quantum description of the particles. In this talk, I will first discuss the HBT effect for thermal light and the laser passing through rotating ground glass.

Both cases give rise to the incoherent radiation. Secondly, I will move on towards the theory of the delayed- choice quantum eraser with incoherent light, in which the interference pattern can still be retrieved.

In a Young's double-slit interferometer, the common "understanding" is that the position-momentum uncertainty relation makes it impossible to determine which slit a photon or wave packet passes through without at the same time disturbing the photon or wave packet enough to destroy the interference pattern. However, in 1982, Scully and Drühl showed that a "quantum eraser" may erase the which-path information even after the annihilation of the quantum itself and determine its early behavior of wavelike or particlelike. This has been experimentally demonstrated with entangled photons. We then recently showed that the quantum eraser scheme can also be realized by measuring the photon-number fluctuation correlation of thermal light.