Finger-gate manipulated quantum transport in Dirac materials.

Area of Science:

• Condensed Matter Physics
• Quantum Mechanics
• Materials Science

Background:

• Understanding quantum transport in nanostructured materials is crucial for developing next-generation electronic devices.
• Materials described by the Dirac equation exhibit unique electronic properties relevant to spintronics.
• Control over electron behavior in nanoribbons is essential for device applications.

Purpose of the Study:

• To investigate the quantum transport properties of multichannel nanoribbons under an in-plane magnetic field.
• To explore the role of gate potentials in controlling electron and hole-like quasibound states (QBS).
• To analyze the impact of energy regimes on conductance behavior and spin-dependent transport.

Main Methods:

• Theoretical investigation of quantum transport in nanoribbons described by the Dirac equation.
• Application of in-plane magnetic fields and varying finger-gate potentials (positive and negative).
• Analysis of electron transitions, including intra-subband and inter-subband transitions via QBS.

Main Results:

• Observed dips in conductance in the low energy regime due to intra-subband transitions via electron-like or hole-like QBS.
• Identified double dip structures in the high energy regime attributed to spin-flip and spin-nonflip inter-subband transitions.
• Demonstrated that inverting gate polarity can manipulate spin-polarized electronic transport.

Conclusions:

• Gate potentials effectively control quantum transport phenomena in nanoribbons, leading to distinct conductance features.
• The study highlights the potential for creating tunable spin-polarized transport.
• These findings pave the way for developing controlled spin-switches based on nanoribbon structures.