We　propose　a　scheme　for　realizing　the　beam-splitter-type　coupling　between　two　cavity　modes.　In　the　scheme　a　collection　of　Λ-type　three-level　atoms　are　coupled　with　the　two　cavity　modes　with　large　detunings.　Under　certain　conditions,　the　effective　Hamiltonian　for　the　cavity　modes　describes　the　frequency-up　conversion,　which　is　decoupled　with　the　atomic　system.　The　effective　coupling　strength　increases　with　the　number　of　the　atoms,　which　allows　the　procedure　to　be　completed　in　a　reasonable　time.　The　atoms　have　no　probability　of　being　populated　in　the　excited　states　and　thus　the　scheme　is　insensitive　to　atomic　spontaneous　emission.　©　2007　Elsevier　B.V.　All　rights　reserved.