In- and outbound spreading of a free-particle s-wave.
We show that a free quantum particle in two dimensions with zero angular momentum (s wave) in the form of a ring-shaped wave packet feels an attraction towards the center of the ring, leading first to a contraction followed by an expansion. An experiment to demonstrate this effect is also outlined.
Białynicki-Birula
I
I
Center for Theoretical Physics, Polish Academy of Sciences, Aleja Lotników 32/46, 02-668, Warsaw, Poland.
Cirone
M A
MA
Dahl
J P
JP
Fedorov
M
M
Schleich
W P
WP