Unveiling the Nature of Genuine Many-Particle Phenomena
Quantum Interference and Complementary Relations Wave-particle duality has been considered a cornerstone of quantum theory, distinguishing the quantum from the classical realm. In the light of multi-particle interference, the transition from quantum to classical many-particle behavior is induced by reducing the coherence properties in the particles' evolution. Although the established theory of many-particle (de)coherence is still developing, experiments have repeatedly demonstrated the increased vulnerability of many-particle coherences as the number of particles grows. These coherence properties are continuously tunable by the level of distinguishability among particles. In our approach, the distinguishability of the particles' evolutions, arising from their internal degrees of freedom, disrupts the ambiguity in how the particles are arranged to form the output state. These arrangements are governed by the unitary transformation matrix that describes their joint evolution. However, optimizing higher-dimensional unitary evolution to achieve multi-particle interference in a suitably chosen measurement setup presents a challenging task.
Many-particle quantum states have attracted paramount interest in both observing and testing the fundamental understanding of quantum physics and advancing quantum information science and technology. As multi-particle interference phenomena form the foundation for quantum random sampling (one of the leading proposals for computational superiority demonstration) and quantum-enhanced information processors, a deeper understanding of many-particle evolution behavior and complementarity relations will help benchmark increasingly complex quantum computation platforms. Moreover, the simulations and measurements on photonic systems proposed in this project will explore analogies with other physical systems, such as cold atoms, potentially leading to broader applications and insights across various fields.