title: Coherent phonon control via electron-lattice interaction in ferromagnetic Co/Pt multilayers.
abstract: The manipulation of coherent phonons in condensed systems has attracted fundamental interest, particularly for its applications to future devices. We demonstrate that a coherent phonon in Co/Pt nano-multilayer can be quantitatively controlled via electron-lattice coupling, specifically by changing the multilayer repeat number. To that end, systematic measurement of the time-resolved reflectivity and magneto-optical Kerr effect in Co/Pt multilayers was performed. The coherent phonon frequency was observed to be shifted with the change of the multilayer repeat number. This shift could be clearly explained based on the two-temperature model. Detailed analysis indicated that the lattice heat capacity and electron-lattice coupling strength are linearly dependent on the repeat number of the periodic multilayer structures. Accessing the control of coherent phonons using nanostructures opens a new avenue for advanced phonon-engineering applications.
authors.affiliation: Department of Physics &Center for Attosecond Science and Technology, POSTECH, Pohang 376-73, South Korea.|Max Planck Center for Attosecond Science, Max Planck POSTECH/KOREA Research Initiative, Pohang, 376-73, South Korea.
authors.forename: Chul Hoon
authors.initials: CH
authors.lastname: Kim
authors.affiliation: Department of Physics &Center for Attosecond Science and Technology, POSTECH, Pohang 376-73, South Korea.|Max Planck Center for Attosecond Science, Max Planck POSTECH/KOREA Research Initiative, Pohang, 376-73, South Korea.
authors.forename: Je-Ho
authors.initials: JH
authors.lastname: Shim
authors.affiliation: Department of Material Science and Engineering and Graduate School of Energy Science and Technology, Chungnam National University, Daejeon 305-764, South Korea.
authors.forename: Kyung Min
authors.initials: KM
authors.lastname: Lee
authors.affiliation: Department of Material Science and Engineering and Graduate School of Energy Science and Technology, Chungnam National University, Daejeon 305-764, South Korea.
authors.forename: Jong-Ryul
authors.initials: JR
authors.lastname: Jeong
authors.affiliation: Department of Physics, Chungbuk National University, Cheongju 361-763, South Korea.
authors.forename: Dong-Hyun
authors.initials: DH
authors.lastname: Kim
authors.affiliation: Department of Physics &Center for Attosecond Science and Technology, POSTECH, Pohang 376-73, South Korea.|Max Planck Center for Attosecond Science, Max Planck POSTECH/KOREA Research Initiative, Pohang, 376-73, South Korea.
authors.forename: Dong Eon
authors.initials: DE
authors.lastname: Kim