We　propose　to　generate　localized　artificial　magnetic　fields　using　two　thin　Raman　laser　beams　intersected　at　a　narrow　region　of　a　two-leg　ladder,　where　the　frequency　difference　must　approximately　match　the　energy　offset　between　the　two　legs.　Based　on　this　method,　we　investigate　the　single-atom　transport　in　a　two-leg　ladder　with　only　two　rungs,　which,　together　with　the　legs,　enclose　a　localized　artificial　magnetic　flux.　Here,　the　atoms　on　the　two　legs　(channels)　possess　different　onsite　energies　that　produce　another　energy　offset.　We　find　that　the　atom　incoming　from　the　left　channel　can　experience　from　blockade　to　transparency　via　modifying　the　onsite　energy,　tunneling　strength,　or　magnetic　flux,　which　can　be　potentially　used　for　a　quantum　switcher.　Furthermore,　the　atom　incoming　from　the　left　channel　can　also　be　perfectly　routed　into　the　right　leg,　when,　intriguingly,　the　outgoing　atom　in　the　right　channel　possesses　a　quasimomentum　that　can　be　modulated　by　the　magnetic　flux.　The　result　may　be　potentially　used　for　the　interface　that　controls　the　communication　between　two　individual　quantum　devices　of　cold　atoms.　The　method　can　also　be　generalized　to　other　artificial　quantum　systems,　such　as　superconducting　quantum　circuit　systems,　optical　systems,　etc.　©　2020　authors.　Published　by　the　American　Physical　Society.