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تسجيل مستخدم جديدUltrafast Dynamic Metallization of Dielectric Nanofilms by Strong Single-Cycle Optical Fields
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We predict a dynamic metallization effect where an ultrafast (single-cycle) optical pulse with a field less or on the order of 1 V/Angstrom causes plasmonic metal-like behavior of a dielectric film with a few-nm thickness. This manifests itself in plasmonic oscillations of polarization and a significant population of the conduction band evolving on a femtosecond time scale. These phenomena are due a combination of both adiabatic (reversible) and diabatic (for practical purposes irreversible) pathways.
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We introduce an effect of metallization of dielectric nanofilms by strong, adiabatically varying electric fields. The metallization causes optical properties of a dielectric film to become similar to those of a plasmonic metal (strong absorption and
negative permittivity at low optical frequencies). The is a quantum effect, which is exponentially size-dependent, occurring at fields on the order of 0.1 V/A and pulse durations ranging from ~ 1 fs to ~ 10 ns for film thickness 3 to 10 nm.
We introduce an effect of metallization of dielectric nanofilms by strong, adiabatically varying electric fields. The metallization causes optical properties of a dielectric film to become similar to those of a plasmonic metal (strong absorption and
negative permittivity at low optical frequencies). The is a quantum effect, which is exponentially size-dependent, occurring at fields on the order of 0.1 V/A and pulse durations ranging from ~ 1 fs to ~ 10 ns for film thickness 3 to 10 nm.
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