Fabrication of thin-film-type terahertz-wave oscillators using intrinsic Josephson junctions

为了利用高温超导Bi2212本征约瑟夫森结实现薄膜太赫兹(THz)波振荡器，研究了如下关键技术：在金属-有机分解法制备的Bi2212薄膜中沉积表面光滑的CeO2缓冲层以增大晶粒度。根据耦合Sine-Gordon方程的解析解，计算了用于设计天线耦合振荡器的结阻抗。此外，利用太赫兹傅里叶变换光谱仪测量的辐射功率和频率的偏置依赖关系，估计了Bi2212台面中的共振模式。这些结果对制备高功率的薄膜太赫兹波振荡器有一定的参考价值。

To realize thin-film-type terahertz (THz)-wave oscillators using high-temperature superconducting Bi-2212 intrinsic Josephson junctions, key technologies were developed as follows: Cerium dioxide buffer layers with a smooth surface were deposited to increase grain sizes in Bi-2212 thin films fabricated by metal-organic decomposition. A junction impedance for designing antenna-coupled oscillators was calculated from an analytical solution of the coupled sine-Gordon equation. Moreover, resonant modes in a Bi-2212 mesa were estimated from bias dependencies of the radiation power and frequency measured using a THz Fourier-transform spectrometer. These results are useful for fabricating the thin-film THz-wave oscillators for high power generation.