Robust Generation of Four-Mode Entangled States through Adiabatic Passages

We propose a robust scheme to generate four-mode entangled states by using the method of adiabatic passage. Our scheme is more insensitive to certain practical sources of noise, such as randomness in the atom's position, atomic spontaneous emission. In addition, the Rabi frequencies of the classical field and interaction time need not to be accurately adjusted as long as the adiabatic condition is fulfilled. The fidelity for the prepared state is higher than 0.97 under current experimental parameters.