Design of topological micropillar cavities for Purcell enhanced single photon emission from semiconductor quantum dots

Semiconductor self-assembled quantum dots offer distinct advantages in generating near-optimal single photons, which have important applications in quantum communication and linear optical quantum computation. Semiconductor quantum dot single-photon sources in the telecommunication band are garnering significant attention due to their considerable advantages in low-loss long-distance fiber transmission. In this paper, we propose and design a topological micropillar cavity based on the interface states between two one-dimensional photonic crystals with distinct Zak phases, achieving a high-quality factor exceeding 15,000 and a significant Purcell factor of up to 606 in the 1.31-µ m band. We have computed the emission efficiency by an InAs/GaAs quantum dot coupled to an arbitrarily detuned single-mode topological micropillar cavity, taking into account pure dephasing processes and the ratio of external-to-internal cavity losses. Our results demonstrate that the designed topologically protected micropillar single-photon sources exhibit robust single-photon emission with high efficiency of over 90% even in the highly dephasing and detuning conditions, which is in striking contrast to the conventional micropillar single-photon sources. Our study provides theoretical guidance for the development of a new type of surface-emitting single-photon source with high performance.