Free-space quantum key distribution(QKD)offers broader geographical coverage and more flexible system deployment than fiber-based systems.However,the free-space environment is highly complex,and various attenuation fa...Free-space quantum key distribution(QKD)offers broader geographical coverage and more flexible system deployment than fiber-based systems.However,the free-space environment is highly complex,and various attenuation factors can significantly reduce the key distribution efficiency or even lead to encoding failures.This paper discusses and analyzes the impact of turbulence and fog in mountainous environments on free-space discrete-variable quantum key distribution.Through numerical simulation,this study examines the effects of altitude and visibility on transmittance and turbulence intensity,finding that turbulence intensity decreases with increasing altitude while transmittance increases;improvements in visibility also lead to increased transmittance.Beam wandering due to turbulence is also dominant.Combining these factors,the effects on the total transmittance and the secret key rate are taken into consideration.Our work could provide a reference for the deployment of practical QKD systems in actual mountainous environments.展开更多
文摘Free-space quantum key distribution(QKD)offers broader geographical coverage and more flexible system deployment than fiber-based systems.However,the free-space environment is highly complex,and various attenuation factors can significantly reduce the key distribution efficiency or even lead to encoding failures.This paper discusses and analyzes the impact of turbulence and fog in mountainous environments on free-space discrete-variable quantum key distribution.Through numerical simulation,this study examines the effects of altitude and visibility on transmittance and turbulence intensity,finding that turbulence intensity decreases with increasing altitude while transmittance increases;improvements in visibility also lead to increased transmittance.Beam wandering due to turbulence is also dominant.Combining these factors,the effects on the total transmittance and the secret key rate are taken into consideration.Our work could provide a reference for the deployment of practical QKD systems in actual mountainous environments.