Imaging of heteronuclear molecular structures based on strong-field tomographic scheme

The study of atomic and molecular structure imaging is of great significance in revealing the microscopic nature of matter and promoting the frontier development of materials science and life science. The rapid development of femtosecond laser technology provides a new method for detecting atomic and molecular structures on an ultrafast time scale, such as strong-field tomography scheme. Strong-field tomography uses strong-field driven electron rescattering to detect the structure of oriented molecules. The advantage of this scheme is that it does not require priori knowledge of atomic differential cross-sections. Using the strong-field tomography scheme, the structural extraction of homonuclear diatomic molecules can be realized successfully. However, it is currently unclear whether this imaging scheme is applicable to the heteronuclear molecular system with more complex cross section of the electron. In this work, heteronuclear diatomic molecules are taken for example and the strong-field tomography scheme is used to study the imaging of the molecular structure. By solving the time-dependent Schrödinger equation, the variation of the photoelectron yield with the orientation angle of the molecular axis is obtained. Next, a fitting method for the variation of the photoelectron yields of the heteronuclear molecules with the orientation angle is presented, and then the fitted value of the internuclear separation is obtained. It is found that the fitting result is comparable to the real molecular internuclear separation, indicating that the strong-field tomography scheme is also suitable for the extraction of heteronuclear molecular structural information.