“Tensor power expansions and multiphotonic interference"

Abstract:

Multiphoton interferometry—the generalization of the Hong–Ou–Mandel interferometer to arbitrary numbers of photons and ports—probes interference effects arising from the collective bosonic nature of many-photon wave functions, in contrast to the single-photon interference that characterizes classical interferometry. The corresponding multiphotonic amplitudes, however, become increasingly difficult to compute and visualize as the number of photons and ports grows, especially under conditions of partial indistinguishability. Tensor power expansions provide an alternative and unifying framework to address this complexity by expressing Fock states with fixed mode occupations as optimal expansions in tensor powers of the single-photon input states defining the corresponding classical interferometer. This approach offers several advantages that become increasingly significant in the large-photon-number regime: (1) it provides a clear interpretation of the coarse-grained structure of multiphotonic probability distributions in the language of classical interferometry, (2) it isolates the most relevant contributions to the multiphotonic amplitudes, and (3) it naturally incorporates partial indistinguishability through tensor powers of entangled single-particle states, establishing a direct semiclassical correspondence between single-particle coherence and multiphotonic visibility. In this talk, we introduce the tensor power expansion formalism for multimode multiphotonic interference highlighting its analytical and conceptual advantages.

Bio:

Alonso Botero is an Associate Professor of Physics at Universidad de los Andes (Bogotá, Colombia) as a member of the Quantum Optics group. He obtained his Ph.D. from The University of Texas at Austin, under the co-supervision of Yakir Aharonov and Yuval Ne’eman. His research spans quantum measurement theory, quantum information theory, mathematical physics and statistical mechanics. His recent interests have concentrated on the large-N asymptotics of representation theory and its applications to multipartite entanglement and multiphotonic interference.