Staircase in the electron mobility of a ZnO quantum dot assembly due to shell filling.
Electron transport in an assembly of ZnO quantum dots has been studied using an electrochemically gated transistor. The electron mobility shows a stepwise increase as a function of the electron occupation per quantum dot. When the occupation number is below two, transport occurs by tunneling between the S orbitals. Transport becomes 3 times faster when the occupation number is between two and eight; tunneling now occurs between the P orbitals. Electron transport is thus critically determined by the quantum properties of the building blocks.
Roest
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Debye Institute, Utrecht University, P.O. Box 80000, 3508 TA Utrecht, The Netherlands.
Kelly
J J
JJ
Vanmaekelbergh
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D
Meulenkamp
E A
EA