Topological phase change transistors based on tellurium Weyl semiconductor

Abstract

Modern electronics demand transistors with extremely high performance and energy efficiency. Charge-based transistors with conventional semiconductors experience substantial heat dissipation because of carrier scattering. Here, we demonstrate low-loss topological phase change transistors (TPCTs) based on tellurium, a Weyl semiconductor. By modulating the energy separation between the Fermi level and the Weyl point of tellurium through electrostatic gate modulation, the device exhibits topological phase change between Weyl (Chern number ≠ 0) and conventional (Chern number = 0) semiconductors. In the Weyl ON state, the device has low-loss transport characteristics due to the global topology of gauge fields against external perturbations; the OFF state exhibits trivial charge transport in the conventional phase by moving the Fermi level into the bandgap. The TPCTs show a high ON/OFF ratio (10 8 ) at low operation voltage (≤2 volts) and high ON-state conductance (39 mS/μm). Our studies provide alternative strategies for realizing ultralow power electronics.

Layer-controlled evolution of electron state in the silicene intercalation compound SrSi2

“…The chiral state allows for information to be carried and encoded without heat dissipation; first field-effect chirality devices emerge. 36,37 The present work establishes a natural limit to miniaturization of such devices. The culprit is various localization phenomena, also controlled by the number of MLs.…”

“…35 Chiral anomaly devices have been demonstrated experimentally. 36,37 In particular, a topological phase change transistor with a high ON/OFF ratio (10 8 ) at low operation voltage and high ON-state conductance demonstrates better performance than conventional charge-based FETs and emerging spin/valley FETs. 37…”

“…35 Chiral anomaly devices have been demonstrated experimentally. 36,37 In particular, a topological phase change transistor with a high ON/OFF ratio (10 8 ) at low operation voltage and high ON-state conductance demonstrates better performance than conventional charge-based FETs and emerging spin/valley FETs. 37 Weyl semimetals play a prominent role in both theoretical 38,39 and experimental 29,40 studies of the chiral anomaly.…”

“…36,37 In particular, a topological phase change transistor with a high ON/OFF ratio (10 8 ) at low operation voltage and high ON-state conductance demonstrates better performance than conventional charge-based FETs and emerging spin/valley FETs. 37 Weyl semimetals play a prominent role in both theoretical 38,39 and experimental 29,40 studies of the chiral anomaly. At the same time, the chiral anomaly has been detected in a number of nodal-line semimetals as well and can be expected in SrSi 2 .…”

Room-temperature valley transistors for low-power neuromorphic computing

“…Compared to the tested valley transport in topological semimetals 14,25 , the modulation of E F and valley transport in Weyl semiconductor is more efficient due to the tunable carrier density (Supplementary Table 1). Te is a Weyl semiconductor that can exhibit exotic transport behaviours from the Weyl point and non-trivial Berry curvature 23,26 . The intrinsic defects of Te make its E F near the valence band maximum 23,27 , which results in a small energy separation (Δε of about 20 meV) between the E F and the Weyl point (Supplementary Fig.…”