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研究方向

场发射X射线源


简介:      

        基于纳米材料的场发射冷阴极X射线源是近几年出现的,被认为是可以取代热阴极技术的具有革命性的新型X射线源技术,具有高空间分辨、高时间分辨、低功耗且易于集成等诸多优势。这些优势将给X射线技术带来新的突破。例如,利用冷阴极技术,可以很容易的实现微焦点X射线源,这在工业检测,相位衬度成像,生命科学研究等领域有重要领用。另外一个最具潜力的方向是基于冷阴极的X射线源阵列的静态多源CT。这种CT技术以电子式的扫描取代传统的机械转动来获取不同角度的图像,可消除机械转动带来的成像伪影,缩短扫描时间,从而减少病人的辐射剂量,并提高对动态物体的成像精度,如跳动的心脏等。而对心脏清晰成像仍是目前CT技术的难点。

        经过多年研究,课题组制备出性能优异的碳纳米管场发射阵列。碳纳米管阵列的场发射性能,包括电流密度,电子发散度,稳定性和寿命等,均已达到国际领先水平。目前,课题组已经研制出碳纳米管冷阴极微焦点X射线源,并结合自主开发的三维成像算法,获得了国内首张冷阴极X射线三维成像图。下一步,课题组将进一步优化射线源系统,并利用这个平台技术,实现多样化整机系统集成。


代表性论文:

1. Shenghan Zhou, Ke Chen, Matthew Thomas Cole, Zhenjun Li, Mo Li, Jun Chen, Christoph Lienau,* Chi Li,* and Qing Dai*. Ultrafast Electron Tunneling Devices—From Electric-Field Driven to Optical-Field Driven. Advanced Materials. 2021,33(35): 2101449

2. Shenghan Zhou, Ke Chen, Xiangdong Guo, Mattew Thomas Cole, Yu Wu, Zhenjun Li, Shunping Zhang,Chi Li, Qing Dai. Antenna-coupled vacuum channel nano-diode with high quantum efficiency. Nanoscale. 2020, 12(3): 1495-1499

3. Chi Li#, Ke Chen#, Mengxue Guan#, Xiaowei Wang, Xu Zhou, Feng Zhai, Jiayu Dai, Zhenjun Li, Zhipei Sun, Sheng Meng*, Kaihui Liu*, Qing Dai* .Extreme nonlinear strong-field photoemission from carbon nanotubes. Nature Communications. 2019, 10:4891

4. Shenghan Zhou#, Ke Chen#, Matthew Thomas Cole, Zhenjun Li,Jun, Chen,Chi Li,* and Qing Dai*. Ultrafast Field-Emission Electron Sources Based on Nanomaterials. Advanced Materials. 2019: 201805845

5. Xiang Liu, Wenxing Zhou, Yuan Tao, Lei Mao, Jianhua Chang, Hai Hu,* Chi Li,*and Qing Dai*, Narrow-Band QD-Enhanced PIN Metal-Oxide Heterostructure Phototransistor with the Assistance of Printing Processes, Advanced Optical Materials, 2019, 1901472, DOI: 10.1002/adom.201901472.

6. Xiang Liu,* Wenjian Kuang, Haibin Ni, Zhi Tao, Jianhua Chang, Qinquan Liu, Junxiang Ge, Chi Li,* and Qing Dai*. High Efficiency Light-Emitting Transistor with Vertical Metal–Oxide Heterostructure. Small. 2018, 14(22): 1800265

7. Chi Li#, Xu Zhou#, Feng Zhai, Zhenjun Li, Fengrui Yao, Ruixi Qiao, Ke Chen, Matthew Thomas Cole, Dapeng Yu, Zhipei Sun*, Kaihui Liu*, and Qing Dai*. Carbon Nanotubes as an Ultrafast Emitter with a Narrow Energy Spread at Optical Frequency. Advanced Materials, 2017, 29(30): 1701580

8. Chi Li , Zhenjun Li , Ke Chen , Bing Bai , Qing Dai*, Edge effect enhanced photo-thermionic emission from a carbon nanotubes array, Applied Physics Letters, 2017, 110: 093105

9. Chi Li#, Xu Zhou#, Feng Zhai, Zhenjun Li,Fengrui Yao, Ke Chen, Dapeng Yu,Zhipei Sun*, Kaihui Liu*, Qing Dai*. Quiver-quenched optical-field-emission from carbon nanotubes, Applied Physics Letters, 2017, 111, 133101

10. Chi Li, Zhenjun Li, Ke Chen, Bing Bai, Qing Dai *, Electrical Driven Light Emitting From a Tunneling Junction With Negative Resistance Effect, IEEE Journal of The Electron Devices Society, 2017, 5(4): 271-274