报告题目 (Title):强场中分子离子的产生、演化及辐射
报告人 (Speaker):谢红强(东华理工大学)
报告时间 (Time):2025年11月18日 (周二) 14:00-16:00
报告地点 (Place):腾讯会议128-831-323
邀请人 (Inviter):戴晔
主办部门:理学院物理系
摘要
(Abstract):Ions represent one of the most abundant products when atoms
or molecules interact with an intense femtosecond laser field.
Nevertheless, our current understanding of their quantum properties
remains limited. Over the past decade, the observation of coherent
ultraviolet-to-visible emissions from nitrogen molecular ions generated
via strong-field ionization has sparked growing interest in ion-related
physics. Significant efforts have been devoted to uncovering the
mechanisms behind these novel laser-like radiations and exploring their
potential applications, such as in remote atmospheric sensing.
Interestingly, the N₂⁺ system exhibits a “kaleidoscopic” nature,
allowing experimenters to observe a variety of phenomena under different
laser parameters—yet this very diversity complicates the interpretation
of the underlying physical processes. In this talk, I will present
recent advances in elucidating the complex physical mechanism behind
ionic lasing from multiple perspectives—a topic of ongoing debate in the
field. By introducing a strong-field ionization-coupling model that
accounts for electronic, vibrational, and rotational states, we are able
to fully characterize ionic dynamics in intense laser fields. This
model provides a unified physical picture for the emergence of N₂⁺
lasing. Furthermore, I will discuss the development of a stimulated and
coherent Raman scattering technique based on ionic air lasing, which
enables non-invasive, high-sensitivity detection of trace gases and air
pollutants.