Tailoring two-photon interference with phase dispersion

Abstract

We present a complete analytical formalism of the effect of phase dispersion on the Hong-Ou-Mandel dip with cw pumping, including higher-order terms. We show that the Hong-Ou-Mandel dip is strongly modified by the frequency-dependent phase modulation and even becomes a bump when the phase dispersion is a special step function. We also show that the phase dispersion function can be fully reconstructed via Fourier transformation from the measurement result of the Hong-Ou-Mandel dip when the dispersion function is antisymmetric. An experimental demonstration of the proposed method using a bandpass filter as a test sample is also presented. The two-photon interference phenomenon with a beam splitter was first demonstrated by Hong, Ou, and Mandel HOM1. They used a pair of photons generated via spontaneous parametric downconversion SPDC, in which a single photon of a pumping laser is converted into a pair of photons. These two photons were sent to a 50-50 beam splitter and were detected by single-photon counters after the beam splitter. They measured the number of coincidence events while scanning an optical delay added to the path of one of the photons, and found a sharp dip a HOM dip ,a t which the delay was exactly zero. This two-photon interference phenomenon has become an important tool 2 in a variety of fields. In the field of quantum information, the phenomenon is used in Bell-state analyzers 3 for quantum teleportation 4 and in quantum gates 5,6 and quantum filters 7 for linear optics quantum computation 8. Recently, this phenomenon has come to be used in the field of optical tomography 9. The effect of phase dispersion on two-photon interference, or the HOM dip, has also been attracting attention because the phase dispersion shows interesting characteristics of the phenomenon and of the downconverted photon pairs. Franson 10 analyzed the effect of dispersion up to the second order and found that the width of the HOM dip and