title: All-Optical Reconstruction of Crystal Band Structure.
abstract: The band structure of matter determines its properties. In solids, it is typically mapped with angle-resolved photoemission spectroscopy, in which the momentum and the energy of incoherent electrons are independently measured. Sometimes, however, photoelectrons are difficult or impossible to detect. Here we demonstrate an all-optical technique to reconstruct momentum-dependent band gaps by exploiting the coherent motion of electron-hole pairs driven by intense midinfrared femtosecond laser pulses. Applying the method to experimental data for a semiconductor ZnO crystal, we identify the split-off valence band as making the greatest contribution to tunneling to the conduction band. Our new band structure measurement technique is intrinsically bulk sensitive, does not require a vacuum, and has high temporal resolution, making it suitable to study reactions at ambient conditions, matter under extreme pressures, and ultrafast transient modifications to band structures.
authors.affiliation: Department of Physics, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada.
authors.forename: G
authors.initials: G
authors.lastname: Vampa
authors.affiliation: Department of Physics, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada.
authors.forename: T J
authors.initials: TJ
authors.lastname: Hammond
authors.affiliation: INRS-EMT, 1650 Boulevard Lionel-Boulet, CP 1020, Varennes, Québec J3X 1S2, Canada.
authors.forename: N
authors.initials: N
authors.lastname: Thiré
authors.affiliation: INRS-EMT, 1650 Boulevard Lionel-Boulet, CP 1020, Varennes, Québec J3X 1S2, Canada.
authors.forename: B E
authors.initials: BE
authors.lastname: Schmidt
authors.affiliation: INRS-EMT, 1650 Boulevard Lionel-Boulet, CP 1020, Varennes, Québec J3X 1S2, Canada.
authors.forename: F
authors.initials: F
authors.lastname: Légaré
authors.affiliation: Department of Physics, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada.
authors.forename: C R
authors.initials: CR
authors.lastname: McDonald
authors.affiliation: Department of Physics, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada.
authors.forename: T
authors.initials: T
authors.lastname: Brabec
authors.affiliation: National Research Council of Canada, Ottawa, Ontario K1A 0R6, Canada.
authors.forename: D D
authors.initials: DD
authors.lastname: Klug
authors.affiliation: Department of Physics, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada.|National Research Council of Canada, Ottawa, Ontario K1A 0R6, Canada.
authors.forename: P B
authors.initials: PB
authors.lastname: Corkum