Integrated photonic circuits for quantum contextuality tests

Fundamental properties of quantum mechanics have been always a topic of interest in both theoretical and experimental physics. Contextuality especially, in the past few years, has been pointed out as the possible reason behind the supremacy of quantum computation. By contextuality we mean the dependence of a physical quantity on its measurement context, that is represented by the different compatible observables that are measured at the same time. It appears as a property of a system when a deterministic model is applied to explain a quantum mechanical experiment. The work of this thesis aims to show a violation of the notorious CHSH contextual inequality within the field of integrated quantum photonics. The experimental setup was divided in two different chips fabricated by femtosecond laser micromachining. The first chip had the purposes of encoding two qubits in a four level state by distributing a single photon in four distinct waveguides. The measurement stage was composed by the second chip, that contains the waveguide circuits representing the needed observables, and by four single photon detectors. By measuring the distribution probabilities of detecting a photon at the output of each measurement device, a violation of the classical inequality was successfully achieved.