Variable wave length laser light source of free electron with carbon nano-tube

碳纳米管以其长电子平均自由程而闻名。在本研究中，周期性磁场垂直作用于碳纳米管。由于电子与周期性磁场之间的相互作用，研究了产生相干微波或光的可能性。本研究的基础是碳纳米管在电极间的排列和周期磁场的合理设计。已经开发出一种简单的方法来排列碳纳米管在电极之间。此外，利用软磁和硬磁薄膜之间的交换耦合在电极之间形成条状畴。由于电极与碳纳米管之间的电阻较大，实验中无法观察到相干光。未来的工作将集中在最小化电极和碳纳米管之间的电阻上。

Carbon nanotubes are well known for its long electron mean free path. In this research, a periodical magnetic field is applied vertical to the carbon nanotube. The possibilities of creation of coherent microwaves or light due to the interactions between electrons and the periodical magnetic field have been investigated. The fundamental of this research are aligning carbon nanotubes between the electrode and suitable design of periodical magnetic field. An easy process has been developed to align carbon nanotubes between the electrodes. Furthermore, exchange coupling between soft and hard magnetic thin film was used to creating strip domains between the electrodes. Due to the large resistance between the electrode and carbon nanotubes, coherent light could not be observed in the experiment. Future works will focus onto the minimization of the resistance between the electrode and carbon nanotubes.