Coherent time evolution of a single-electron wave function.
Observation of coherent single-electron dynamics is severely limited by experimental bandwidth. We present a method to overcome this using moving quantum dots defined by surface acoustic waves. Each dot holds a single electron, and travels through a static potential landscape. When the dot passes abruptly between regions of different confinement, the electron is excited into a superposition of states, and oscillates unitarily from side to side. We detect these oscillations by using a weak, repeated measurement of the current across a tunnel barrier, and find close agreement with simulations.
Kataoka
M
M
Cavendish Laboratory, Cambridge CB3 0HE, United Kingdom.
Astley
M R
MR
Thorn
A L
AL
Oi
D K L
DK
Barnes
C H W
CH
Ford
C J B
CJ
Anderson
D
D
Jones
G A C
GA
Farrer
I
I
Ritchie
D A
DA
Pepper
M
M