Study Gravitational Lensing of the Cosmic Microwave Background by Galaxy Clusters

The CMB lensing signal by the galaxy clusters has been recently detected significantly.  The measurements of this signal can be used to calibrate the masses of the galaxy clusters complementary to other calibration methods.  I will present the resent detection results with introduction of the methods we use to characterize this signal.  The measurement of CMB cluster lensing effect requires better understanding of the systematics, especially the astrophysical signals that contaminate the CMB lensing signal at cluster scales, such as thermal-SZ, kinetic-SZ, CIB, and large-scale structures.  I will also discuss the plan and the current progress on investigating these systematics.