Effect of thermal inhomogeneity for terahertz radiation from intrinsic Josephson junction stacks of Bi[2]Sr[2]CaCu[2]O[8]+δ

Abstract

Terahertz radiation from the mesa structures of Bi[2]Sr[2]CaCu[2]O[8]+ δ is detected in samples with thin electrodes <100 nm. In samples with thick electrodes≃400 nm, neither radiations nor voltage jumps in current-voltage characteristics are detected. This suggests that the thin electrode helps excite the Josephsonplasma oscillation as a result of the poor heat flow through the electrode. The shielding effect by the electrode is not essential. We consider that the local temperature rise is the origin of the synchronization of the phase kink for terahertz radiation.