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Semimetallization of dielectrics in strong optical fields
Ojoon Kwon1,2, Tim Paasch-Colberg3, Vadym Apalkov4
1Department of Physics, Center for Attosecond Science and Technology, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea.
Scientific Reports
|February 19, 2016
Summary
Ultrafast optical fields induce reversible semimetallization in dielectrics like sapphire and quartz. This phenomenon, driven by Wannier-Stark localization, suggests potential for petahertz optoelectronics.
Area of Science:
- Solid-state physics
- Ultrafast optics
- Materials science
Background:
- Semiconductor research is driven by the need for faster signal processing.
- Intense optical fields enable novel phenomena and applications in solids.
- Femtosecond optical fields offer potential for petahertz optoelectronic devices.
Purpose of the Study:
- To investigate the universality of strong-field-induced semimetallization in dielectrics.
- To compare the semimetallization phenomenon in sapphire, calcium fluoride, and quartz.
- To explore the potential for petahertz optoelectronics.
Main Methods:
- Employing a carrier-envelope-phase stabilized, few-cycle strong optical field.
- Inducing and observing semimetallization in sapphire, calcium fluoride, and quartz.
- Analyzing the material response to strong optical fields on a femtosecond timescale.
Main Results:
- Demonstrated reversible semimetallization in sapphire, calcium fluoride, and quartz.
- Observed remarkable similarity in the semimetallization phenomenon across different dielectrics.
- Attributed the ultrafast semimetallization to strong Wannier-Stark localization and Zener-type tunneling.
Conclusions:
- The strong-field-induced semimetallization in dielectrics exhibits universal behavior.
- Wannier-Stark state localization provides a consistent physical explanation for the observed phenomenon.
- These findings pave the way for developing petahertz-rate optoelectronic devices.
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