Manipulation of Transverse Photonic Degrees of Freedom Via Classical and Hong-Ou-Mandel Interference

Aruto Hosaka

Cody C. Leary, Maggie Lankford, Deepika Sundarraman

We investigate the connection between biphoton states involving photons in product modes of their spin and orbital degrees of freedom and those involving photons in hybrid spin-orbit modes, as mediated by Hong-Ou-Mandel interference (HOMI) in an asymmetric Mach-Zehnder interferometer. We predict that two input photons in balanced superposition states of both their spin and orbital degrees of freedom will exhibit HOMI while undergoing a simultaneous mode conversion from product spin-orbit input modes to hybrid output modes bearing orbital angular momentum. These hybrid outputs contain a spatially varying polarization structure which may be controllably rotated about the photonic beam axis by varying the relative phase between the vertical and horizontal components of each input photon's polarization. Additionally, a type of coupling of the spin and orbital degrees of freedom is exhibited in this system: the transverse spatial profile of the output photons may be continuously manipulated by tuning the polarization parameters of the input photons, in such a way that the HOMI between the photons remains stable. An interesting corollary to this work is the possibility of demonstrating in a simple experimental system that HOMI may occur between distinguishable input modes.

Ebrahim Karimi, Daniel Giovannini, Eliot Bolduc +4 more

In quantum information, quantum systems and their properties offer unprecedented opportunities. Being able to harness additional degrees of freedom adds power and flexibility to quantum algorithms and protocols. In this work, we demonstrate that the radial transverse mode of a single photon constitutes one such degree of freedom. We do so by showing that we can tune the two-photon interference, a quintessential quantum effect and the basic constituent of many quantum protocols, by manipulating its radial transverse modal profiles. Our work, in addition to allowing for greater versatility of existing protocols and significantly increasing the information channel capacity, can inspire novel quantum information tasks.

Qiuying Li, Minggui Liang, Jiawei Liu +6 more

Hui‐Ming Wang, Mingyuan Chen, Yuan Chen +12 more

Agata M. Brańczyk

This article is a detailed introduction to Hong-Ou-Mandel (HOM) interference, in which two photons interfere on a beamsplitter in a way that depends on the photons' distinguishability. We begin by considering distinguishability in the polarization degree of freedom. We then consider spectral distinguishability, and show explicitly how to calculate the HOM dip for three interesting cases: 1) photons with arbitrary spectral distributions, 2) spectrally entangled photons, and 3) spectrally mixed photons.