The interaction of two quantized fields with an atomic ensemble including N three-level V-type atoms inside a two-mode cavity is investigated. With nonadiabatic elimination, the quantum correlation properties of two output cavity fields are analyzed when the two initial input fields are in coherent states. The results show that the quantum entanglement can be generated at the zero frequency under appropriate conditions. As the cooperation parameter increases, the zero-frequency entanglement decreases, and even vanishes. However, a pair of sideband entanglement happen in the high-frequency regime, which are induced by vacuum Rabi splitting. In addition, by modifying the intensity of the quantized fields and the antisymmetric detunings, two pairs of sideband entanglement can also be obtained. These results will benefit the research of the sideband quantum correlations.