Unraveling Ultrafast Photoionization in Hexagonal Boron Nitride

التفاصيل البيبلوغرافية
العنوان: Unraveling Ultrafast Photoionization in Hexagonal Boron Nitride
المؤلفون: Xue, Lianjie, Liu, Song, Hang, Yang, Summers, Adam M., Wilson, Derrek J., Wang, Xinya, Chen, Pingping, Folland, Thomas G., Hachtel, Jordan A., Shi, Hongyu, Hosseini-Zavareh, Sajed, Das, Suprem R., Lei, Shuting, Zhang, Zhuhua, Sorensen, Christopher M., Guo, Wanlin, Caldwell, Joshua D., Edgar, James H., Blaga, Cosmin I., Trallero-Herrero, Carlos A.
سنة النشر: 2021
المجموعة: Condensed Matter
Physics (Other)
مصطلحات موضوعية: Physics - Optics, Condensed Matter - Other Condensed Matter
الوصف: The non-linear response of dielectrics to intense, ultrashort electric fields has been a sustained topic of interest for decades with one of its most important applications being femtosecond laser micro/nano-machining. More recently, renewed interests in strong field physics of solids were raised with the advent of mid-infrared femtosecond laser pulses, such as high-order harmonic generation, optical-field-induced currents, etc. All these processes are underpinned by photoionization (PI), namely the electron transfer from the valence to the conduction bands, on a time scale too short for phononic motion to be of relevance. Here, in hexagonal boron nitride, we reveal that the bandgap can be finely manipulated by femtosecond laser pulses as a function of field polarization direction with respect to the lattice, in addition to the field's intensity. It is the modification of bandgap that enables the ultrafast PI processes to take place in dielectrics. We further demonstrate the validity of the Keldysh theory in describing PI in dielectrics in the few TW/cm2 regime.
Comment: 13 pages, 4 figures
نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/2101.10429
رقم الأكسشن: edsarx.2101.10429
قاعدة البيانات: arXiv