Faced with China’s great strategic needs in fusion physics, as well as applications in national defense and fusion energy, the SG-II facility is working to develop the application infrastructure and key technology of the laser driver and to integrate it into the system. The SG-II facility will also conduct innovative and exploratory research in high power density physics, study and develop laser driver devices, maintain high efficiency and a high quality facility operation, promote international cooperation and academic exchange, develop talent, and insist on independent innovation and sustainable development. The facility will lead the world in the scientific development and technical progress of laser driver devices, and will be a laser technology research and development centre with international influence.
Currently, as an important component of China’s laser fusion research and development, the scientific objectives and research directions of the SG-II facility lie in the following four areas:
1．Scientific experiments addressing strategic energy needs
Controlled thermonuclear fusion is one effective way to address global energy issues. Over the past few decades, scientists worldwide have made great efforts in the quest to achieve fusion because of its potential ability to safely generate huge amounts of energy.
2．Scientific experiments addressing strategic national security needs
Using the high-temperature and high-density plasma generated from inertial confinement fusion induced by the laser in the lab, multiple physics experiments can be conducted on implosion dynamics, high temperature radiation hydrodynamics and interface instability, shock wave physics, thermonuclear reaction kinetics, and neutronics. Through these studies, basic physical laws important to national security strategy could be better understood and mastered and important physical parameters could be acquired and used to calibrate numerical simulation programs. These studies can help us discover new scientific laws and, therefore, help solve issues related to the reliability and effectiveness of our national security strategy.
3．Scientific experiments involving basic research into high energy density physics
“High energy density physics” is a new dynamic scientific research field that has expanded from inertial confinement fusion research. It is an interdisciplinary research area that includes fluid dynamics, plasma physics, condensed matter physics, high power laser and particle beam physics, the study of high radiation and the matter that interacts with it, and astrophysics. At extremely high pressure and density the internal collective interactions of matter become very complex and non-linear. This complexity and non-linearity are the common characteristics in the fields mentioned above. This presents a great challenge as well as a great opportunity for the human intellect. High power solid laser technology provides a whole new approach for innovation and development in strategic high-tech areas such as laser fusion energy, advanced laser particle acceleration and space laser application development. Meanwhile, it also provides a new research platform and tool that can be used in the development of cutting-edge interdisciplinary science fields such as high energy density physics and laboratory astrophysics.
4．Research and development on new high power laser driver technology
With the increased requirements placed on high power laser drivers in inertial confinement fusion experiments, especially high energy density physics experiments, questions about how to effectively improve the overall energy conversion efficiency of laser devices, the beam quality, and the thermal properties of laser materials have become the key technological issues that must be addressed in order to improve operation efficiency of high power laser drivers.