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Great attention have been payed to the research of semiconductor spintronics to fabricate novel spin-based devices.The advantages of these new devices would be nonvolatility, increased data processing speed, decreased electric power consumption, and increased integration densities compared with conventional semiconductor devices[1].However, it is not an easy task to control the spin degree of freedom of electrons in semiconductors.Spin-orbit coupling(SOI) provides an effective approach to manipulate the spin of electrons by external conditions such as external electric field, stress and etc.In low dimensional system of semiconductors, spin orbit coupling and inverse asymmetry lead to spin split of electron energy bands.Circular photo-galvanic effect(CPGE)[2], magneto-gyrotropic photocurrent effect(MPGE)[3] together with spin hall effect(SHE)[4], all related to spin-orbit coupling effect.These effects have been extensively studied in GaAs/AlGaAs quantum wells[5], AlGaN/GaN heterostructures[6], graphene[7] and so on..In this letter, we studied the circular photo-galvanic effect in InAs/GaSb short period superlattices, which is an important structure for infrared detector.We use mid-infrared laser to excite Drude absorption of carriers and near-infrared laser to excite the interband transition of carriers respectively.We find that the Rashba circularly polarized photocurrents are similar in these two conditions, but the Dresselhaus circularly polarized photocurrent of the Drude absorption is about six times larger than the interband transition condition.