Electromagnetic black holes with controllable composite right/left-handed transmission lines.

Given that the Hawking radiation from celestial black holes is extremely weak and thus difficult to be practically detected, a series of analogue black holes have been constructed to observe the relevant analogue Hawking radiations in the laboratory. Based on the critical behavior of group velocity of the microwave signal propagating along a controllable composite right/left-handed transmission line, in this paper, we theoretically demonstrate that an electromagnetic black hole (EBH) can be constructed in the relevant co-moving coordinate system, i.e.