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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.

SUBMITTER: Kim CH

PROVIDER: S-EPMC4771999 | biostudies-literature | 2016 Mar

REPOSITORIES: biostudies-literature

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Coherent phonon control via electron-lattice interaction in ferromagnetic Co/Pt multilayers.

Kim Chul Hoon CH Shim Je-Ho JH Lee Kyung Min KM Jeong Jong-Ryul JR Kim Dong-Hyun DH Kim Dong Eon DE

Scientific reports 20160301

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 ...[more]

PMID: 26928846

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