Topological phase change transistors based on tellurium Weyl semiconductor

Area of Science:

• Condensed Matter Physics
• Materials Science
• Semiconductor Device Physics

Background:

• Conventional transistors face limitations in performance and energy efficiency due to heat dissipation from carrier scattering.
• Topological materials offer unique electronic properties that can potentially overcome these limitations.

Purpose of the Study:

• To demonstrate a novel low-loss topological phase change transistor (TPCT) utilizing the Weyl semiconductor tellurium.
• To explore the modulation of topological phase and charge transport characteristics via electrostatic gating.

Main Methods:

• Fabrication of transistors based on tellurium, a Weyl semiconductor.
• Electrostatic gate modulation to control the Fermi level relative to the Weyl point.
• Characterization of device performance, including ON/OFF ratio, operation voltage, and ON-state conductance.

Main Results:

• Demonstrated a topological phase change between Weyl (non-zero Chern number) and conventional (zero Chern number) semiconductor states.
• Achieved a high ON/OFF ratio of 10^8 at a low operation voltage (≤2 V).
• Observed high ON-state conductance of 39 mS/μm in the Weyl ON state, attributed to low-loss topological transport.

Conclusions:

• Topological phase change transistors (TPCTs) based on tellurium offer a promising pathway for high-performance, energy-efficient electronic devices.
• Electrostatic control of topological phase provides a viable strategy for designing ultralow power electronics.
• This work presents alternative strategies for advancing semiconductor technology beyond conventional charge-based devices.