We　study　the　quantum　phase　transition　in　the　Dicke　model　beyond　the　thermodynamic　limit.　With　the　Kibble–Zurek　mechanism　and　adiabatic　dynamics,　we　find　that　the　residual　energy　is　inversely　proportional　to　the　number　of　qubits,　indicating　that　more　qubits　can　obtain　more　energies　from　the　oscillator　as　the　number　of　qubits　increases.　Finally,　we　put　forward　a　promising　experiment　device　to　realize　this　system.　©　2020,　The　Author(s).