title: Midinfrared optical breakdown in transparent dielectrics.
abstract: Optical breakdown measurements for transparent dielectrics are reported for 1 ps laser pulses as a function of mid-IR wavelength from 4.7 to 7.8 microm. For wide-gap dielectrics seed electrons are generated by tunnel ionization with subsequent avalanche ionization and laser absorption by dense plasma. For narrow-gap dielectrics tunnel ionization alone leads to dense plasma formation.
authors.affiliation: W. W. Hansen Experimental Physics Laboratory, Stanford University, Stanford, California 94305, USA.
authors.forename: D M
authors.initials: DM
authors.lastname: Simanovskii
authors.forename: H A
authors.initials: HA
authors.lastname: Schwettman
authors.forename: H
authors.initials: H
authors.lastname: Lee
authors.forename: A J
authors.initials: AJ
authors.lastname: Welch