Quantum interference with photon pairs using two micro-structured fibres

Abstract

We demonstrate a quantum interference experiment between two photons coming from non-degenerate pairs created by four-wave mixing in two separated microstructured fibres. When the two heralded photons are made indistinguishable a 95% visibility is demonstrated.

On the genesis and evolution of Integrated Quantum Optics

“…In 2007 and 2009, two fiber-optic solutions have been implemented, one relying on microstructured fibers emitting photons in the visible band associated with 300 pm filters (Bristol University) [33], and the other on DSFs emitting photons in the telecom range associated with 200 pm FBG filters by an NTT group [35]. It is also worth noting the demonstration of intrinsically narrowband fiber sources allowing heralding one photon in a pure spectral state and, hence, rendering narrowband filtering unnecessary [142].…”

High-visibility two-photon interference at a telecom wavelength using picosecond-regime separated sources

“…For instance, the best visibility reported so far in the femtosecond regime has been obtained by compensating the synchronization-induced temporal distinguishability by dramatically increasing the photons coherence time up to a few picoseconds at the expense of the overall brightness [4]. Since laser cavities can easily be synchronized to sub-picosecond accuracy [15,16], the study of the picosecond regime [6,17], its associated filter bandwidths, and the type of photon pair generators, becomes of prime interest to ensure simultaneously a high degree of indistinguishability and a high overall brightness.…”

Nonlinear Optics for Photonic Quantum Networks

“…Compared with standard step-index fibres, PCFs have periodically arranged air holes in the cladding, which significantly increase the index difference between the fibre core and cladding and thus introduce relatively large higher-order dispersion over a broad wavelength range. This makes phase-matching possible when pumping in the normal dispersion regime and many demonstrations have shown low-noise single or entangled photon generation at room temperature in this regime [38,50,[82][83][84][85]. In these demonstrations, the frequencies of generated photons are typically over 70 THz away from that of pump.…”

“…In the pump frequency degenerate SFWM process, the signal and idler photons appear at different wavelengths and are therefore distinguishable. To perform Hong-Ou-Mandel quantum interference, two heralded single-photon sources based on such a SFWM process are required [83][84][85]. This involves four-photon coincidence events, which are significantly less likely to happen and so experiments are much longer and more challenging than those involving two-photon coincident events.…”