title: Vibration-assisted upconversion of molecular luminescence induced by scanning tunneling microscopy.
abstract: : We investigate the effects of coupling between a molecular exciton, which consists of an electron and a hole in a molecule, and a surface plasmon (exciton-plasmon coupling) on the electron transitions of the molecule using nonequilibrium Green's function method. Due to the exciton-plasmon coupling, excitation channels of the molecule arise in the energy range lower than the electronic excitation energy of the molecule. It is found that the electron transitions via these excitation channels give rise to the molecular luminescence and the vibrational excitations at the bias voltage lower than the electronic excitation energy of the molecule. Our results also indicate that the vibrational excitations assist the emission of photons, whose energy exceeds the product of the elementary charge and the bias voltage, (upconverted luminescence).
authors: Department of Applied Physics, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan. kasai@dyn.ap.eng.osaka-u.ac.jp.
authors: Kuniyuki
authors: K
authors: Miwa
authors: Mamoru
authors: M
authors: Sakaue
authors: Hideaki
authors: H
authors: Kasai
references: J Chem Phys. 2008 Jul 7;129(1):014701
references: 18624490
references: Phys Rev Lett. 2004 Feb 27;92(8):086801
references: 14995803
references: Science. 1993 Nov 26;262(5138):1425-7
references: 17736824
references: J Chem Phys. 2009 Apr 14;130(14):144109
references: 19368431
references: Science. 2003 Jan 24;299(5606):542-6
references: 12543968
references: Phys Rev Lett. 2011 Apr 29;106(17):177401
references: 21635061
references: Nanoscale Res Lett. 2011 Apr 19;6(1):347
references: 21711870
references: Phys Rev Lett. 2010 Nov 19;105(21):217402
references: 21231352
references: Phys Rev Lett. 1992 May 25;68(21):3224-3227
references: 10045645