  We theoretically propose a practical method for realizing intense terahertz
(THz) emission from intrinsic Josephson junctions (IJJs) using an external heat
source. An artificial inhomogeneous temperature distribution by the local
heating strongly excites the Josephson plasma wave inside IJJs and enhances THz
emission power. We show optimum heating conditions for achieving high power THz
emission. Our result indicates that local heat control is a powerful method to
realize practical solid-state THz-emitters utilizing IJJs.
