Gate-defined quantum dots on carbon nanotubes.
We report the realization of nanotube-based multiple quantum dots that are fully defined and controlled with electrostatic gates. Metallic top-gates are used to produce localized depletion regions in the underlying tubes; a pair of such depletion regions in a nanotube with ohmic contact electrodes defines the quantum dot. Top-gate voltages tune the transparencies of tunnel barriers as well as the electrostatic energies within single and multiple dots. This approach allows precise control over multiple devices on a single tube, and serves as a design paradigm for nanotube-based electronics and quantum systems.
Biercuk
M J
MJ
Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA.
Garaj
S
S
Mason
N
N
Chow
J M
JM
Marcus
C M
CM
D003460:Crystallization / Q000379:methods*; D004553:Electric Conductivity; D004563:Electrochemistry / Q000295:instrumentation / Q000379:methods*; D036103:Nanotechnology / Q000295:instrumentation / Q000379:methods*; D037742:Nanotubes, Carbon / Q000032:analysis / Q000737:chemistry*; D045663:Quantum Dots; D012666:Semiconductors; D055672:Static Electricity
D037742:Nanotubes, Carbon