Dr. Charles Ci Wen Lim obtained his B.Sc. (Hons) in Physics from NUS in 2010, and his Ph.D. in Quantum Communication Theory from the University of Geneva, Switzerland, in 2014. In 2015, he joined the Computational Sciences and Engineering Division at Oak Ridge National Laboratory, USA. He recently returned to Singapore to join the Department. Dr. Lim’s research is broadly focused on the theory of quantum communication and cryptography. A key feature of his research is the security of quantum cryptosystems. His theoretical contributions in this area have led to the world’s longest distance quantum key distribution experiment (Nature Photonics 9, 163, 2015).