Study of Non-equilibrium Superconductivity in HTSC and Electronic Application

在本项目中，我们研究了新型高T_c氧化物超导材料中可能出现的“非平衡超导电性”，并将这一现象应用到晶体管放大器中。到目前为止，我们的外延薄膜的零电阻温度高达86K，当然，我们在制备多晶薄膜方面没有问题。测试样品是用外延薄膜和多晶薄膜制备的。他们装备了源极和漏极。在沟道中央形成准粒子注入的栅电极，测试样品表现出准粒子注入对沟道电流的调制作用。它们大多在低温下表现出电流放大。理论和实验结果的比较表明，观测到的电流调制一定是由于高温超导体中非平衡超导电性的发展所致。特别是，BCS模型相当合理地解释了观察结果。

In this project, we have investigated the possible occurrence of the "Non-equilibrium Superconductivity" in the new high Tc oxide superconducting materials and applied this phenomenon to the transistor amplifier.We started the work by preparing the epitaxial YBaCuO thin films. So far, our epitaxial films have the zero-resistance temperature as high as 86 K. Off course, we have no problem in making the polycrystalline films. The test samples were fabricated by using both the epitaxial and polycrystalline films. They equipped the source and drain electrodes. At the central portion of the channel, the gate electrode for the quasi-particle injection was formed.The test samples showed the channel current modulation via the injection of the quasi-particles. Most of them exhibited the current amplification at low temperature. Comparison oi the theory with the experimental results indicated that the observed current modulation must be due to the development of the non-equilibrium superconductivity in the high Tc superconductors. Particularly, the BCS model explained the observations quite reasonably.