and J R oscillate with same phase whereas J B vanishes. The time-dependence of ring
current quantum beat originates from the creation of two electronic states, the oscillation period corresponds to a frequency difference of two electronic states. Similarly
0
5 0
1 0 0
1 5 0
-200
-150
-100
-50
0
50
100
150
200
time [fs]
J B
J L
J R
0
5 0
1 0 0
1 5 0
-200
-150
-100
-50
0
50
100
150
200
time [fs]
J B
J L
J R
0
5 0
1 0 0
1 5 0
-200
-150
-100
-50
0
50
100
150
200
time [fs]
J B
J L
J R
Current [ A]
μ
Current [
A]
μ
Current [ A]
μ
(a)
(b)
(c)
Fig. 3 Time dependence of
ring currents and bridge bond
currents created by π pulse
laser excitation with a laser
pulse shape (shaded area):
a for coherent excited states
ða þ b 1 Þ created by a laser
pulse with a magnitude
F = 2.5 GV/m, b for coherent
excited states ða þ b 2 Þ created
by a laser pulse with a
magnitude F = 4.5 GV/m,
c for coherent excited states
ðb 1 þ b 2 Þ created by a laser
pulse with a magnitude
F = 1.2 GV/m. Laser pulse
envelopes are also drawn in
plots of ring currents by green
shaded areas in arbitrary units
Theoretical Study of Coherent π-Electron Rotations …
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