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Orbital Tuning of Tunnel Coupling in InAs/InP Nanowire Quantum Dots
Zahra Sadre Momtaz1, Stefano Servino2, Valeria Demontis1
1NEST, Instituto Nanoscienze CNR and Scuola Normale Superiore, Piazza S. Silvestro 12, I-56127 Pisa, Italy.
Nano Letters
|February 13, 2020
Summary
Researchers controlled barrier transparency in nanowire quantum dots by manipulating electron orbital configurations. This allows for tunable tunneling rates, crucial for quantum device applications.
Area of Science:
- Quantum Information Science
- Condensed Matter Physics
- Nanotechnology
Background:
- Barrier transparency in InAs/InP nanowire quantum dots typically depends on trapped electron orbital energy.
- Previous studies established a general trend for barrier transparency based on total orbital energy.
Purpose of the Study:
- To investigate electrostatic control of barrier transparency in nanowire quantum dots.
- To explore alternative mechanisms for controlling tunneling rates beyond total orbital energy.
Main Methods:
- Utilized electrostatic gating to control electron states in InAs/InP nanowire quantum dots.
- Analyzed tunneling rates by varying electron filling numbers and orbital configurations.
- Compared experimental results with numerical simulations of barrier transparency.
Main Results:
- Identified a distinct regime at low filling numbers where axial electron orbital configuration dominates tunneling rates.
- Demonstrated that electrostatic gating can modify transmission rates by tuning radial orbital configurations.
- Observed that barrier transparency evolves for different orbitals consistent with theoretical predictions.
Conclusions:
- Electrostatic control offers a novel method to tune barrier transparency and tunneling rates in nanowire quantum dots.
- This tunability is essential for precise control over individual Coulomb blockade resonances.
- The findings pave the way for advanced quantum devices utilizing controlled electron tunneling.
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