ausblenden:
Schlagwörter:
NUMBER-RESOLVING DETECTOR; QUANTUM INTERFERENCE; SQUEEZED-LIGHT;
INFORMATION; PAIRS; WAVELENGTHS; GENERATION; DEGENERATE; FIDELITY;
DEVICEOptics; Physics;
Zusammenfassung:
Parametric down-conversion (PDC) is one of the most widely used methods to create pure single-photon states for quantum information applications. However, little attention has been paid to higher-order photon components in the PDC process, yet these ultimately limit the prospects of generating single photons of high quality. In this paper we investigate the impact of higher-order photon components and multiple frequency modes on the heralding rates and single-photon fidelities. This enables us to determine the limits of PDC sources for single-photon generation. Our results show that a perfectly single-mode PDC source in conjunction with a photon-number-resolving detector is ultimately capable of creating single-photon Fock states with unit fidelity and a maximal state creation probability of 25%. Hence, an array of 17 switched sources is required to build a deterministic (>99% emission probability) pure single-photon source.