Vibrationally resolved fluorescence from organic molecules near metal surfaces in a scanning tunneling microscope.
Intrinsic molecular fluorescence from porphyrin molecules on Au(100) has been realized by using a nanoscale multimonolayer decoupling approach with nanoprobe excitation in the tunneling regime. The molecular origin of luminescence is established by the observed well-defined vibrationally resolved fluorescence spectra. The molecules fluoresce at low "turn-on" voltages for both bias polarities, suggesting an excitation mechanism via hot electron injection from either tip or substrate. The excited molecules decay radiatively through Franck-Condon pi(*)-pi transitions.
Dong
Z-C
ZC
National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan.
Guo
X-L
XL
Trifonov
A S
AS
Dorozhkin
P S
PS
Miki
K
K
Kimura
K
K
Yokoyama
S
S
Mashiko
S
S