Final Report Summary - 3D-QUEST (3D-Quantum Integrated Optical Simulation)
The field of Quantum information science aims at investigating the properties of Quantum mechanics and at applying them to improve the performances achievable with classical resources in computational problems. Among the different tasks which can benefit from this approach, Quantum Simulation allows the investigation of several physical phenomena. These include, for instance, the analysis of the role of quantum mechanics in transport phenomena, simulation of quantum dynamics in spin chains or solid state systems, investigation of the quantum-to-classical transition, or the identification of suitable tasks which can be solved more efficiently by adopting a quantum approach. It is then crucial to identify suitable platforms allowing for an experimental implementation of quantum simulation protocols. Among the different proposed systems, integrated photonics presents several advantages due to the recent technological progress, opening new perspectives in the implementation of complex optical networks.
The aim of the 3D-QUEST project is to exploit the capabilities of integrated photonics for Quantum Simulation experiments. The possibility of designing 3-dimensional integrated structures with the femtosecond laser-writing technique allows for the realization of new devices which can be adopted as a building block for new complex architectures. Several tasks are investigated by the 3D-QUEST project. These include the simulation of bosonic-fermionic dynamics with 2-photon entangled states, the observation of multiphoton interference in systems of increasing size, and the implementation of novel 3-dimensional integrated structures. Significant results have been obtained throughout the project.
The observation of Anderson localization for pairs of polarization-entangled photons in a discrete quantum walk affected by position-dependent disorder has been reported, simulating the different bosonic and fermionic dynamics by exploiting the symmetry of the 2-photon wave function.
Furthermore, the observation of how it is possible to enhance the efficiency of a quantum walker to reach the output of a maze by reducing the amount of quantum coherence has been reported.
The first observation of multiphoton interference in Boson Sampling experiments with n=3 photons injected in integrated multiport interferometers has been obtained, including the verification of two general laws which rule bosonic bunching. By using the femtosecond laser writing technique, simultaneous control of all parameters necessary to implement arbitrary interferometers has been achieved. Within this context, first results on the validation of Boson Sampling data against relevant classes of alternative hypotheses have been reported. Furthermore, a modified version with random inputs of the original problem, called Scattershot Boson Sampling, which provides a significant boost in the detected signal, has been realized.
The three-dimensional capabilities of femtosecond laser-writing technique allowed for the implementation of novel devices, such as a three-port symmetric directional coupler, with the experimental observation of three-photon bosonic coalescence. A technique to implement in a scalable and reliable way specific relevant transformation such as the Fourier one has been developed and tested experimentally. This allowed to observe genuine multiparticle interference that in these devices appears as the incapability of observing a significant fraction of input/output combinations.
Within the project, an important step towards the development of fully reconfigurable devices has been achieved. Indeed, it has been shown the capability of implementing tunable phase shift via thermal effects in glass by the femtosecond laser-writing technique, thus opening new perspectives in the realization of complex dynamically-reconfigurable devices.
The aim of the 3D-QUEST project is to exploit the capabilities of integrated photonics for Quantum Simulation experiments. The possibility of designing 3-dimensional integrated structures with the femtosecond laser-writing technique allows for the realization of new devices which can be adopted as a building block for new complex architectures. Several tasks are investigated by the 3D-QUEST project. These include the simulation of bosonic-fermionic dynamics with 2-photon entangled states, the observation of multiphoton interference in systems of increasing size, and the implementation of novel 3-dimensional integrated structures. Significant results have been obtained throughout the project.
The observation of Anderson localization for pairs of polarization-entangled photons in a discrete quantum walk affected by position-dependent disorder has been reported, simulating the different bosonic and fermionic dynamics by exploiting the symmetry of the 2-photon wave function.
Furthermore, the observation of how it is possible to enhance the efficiency of a quantum walker to reach the output of a maze by reducing the amount of quantum coherence has been reported.
The first observation of multiphoton interference in Boson Sampling experiments with n=3 photons injected in integrated multiport interferometers has been obtained, including the verification of two general laws which rule bosonic bunching. By using the femtosecond laser writing technique, simultaneous control of all parameters necessary to implement arbitrary interferometers has been achieved. Within this context, first results on the validation of Boson Sampling data against relevant classes of alternative hypotheses have been reported. Furthermore, a modified version with random inputs of the original problem, called Scattershot Boson Sampling, which provides a significant boost in the detected signal, has been realized.
The three-dimensional capabilities of femtosecond laser-writing technique allowed for the implementation of novel devices, such as a three-port symmetric directional coupler, with the experimental observation of three-photon bosonic coalescence. A technique to implement in a scalable and reliable way specific relevant transformation such as the Fourier one has been developed and tested experimentally. This allowed to observe genuine multiparticle interference that in these devices appears as the incapability of observing a significant fraction of input/output combinations.
Within the project, an important step towards the development of fully reconfigurable devices has been achieved. Indeed, it has been shown the capability of implementing tunable phase shift via thermal effects in glass by the femtosecond laser-writing technique, thus opening new perspectives in the realization of complex dynamically-reconfigurable devices.