Fig. 2: The schematic of TaS2 device, THz detection mechanism and related performance.
From: Reconfigurable terahertz optoelectronic logic through charge-density-wave phase engineering
a Schematic illustration of the THz photodetection setup showing the optical path from laser source through parabolic mirror to the device, with cross-sectional view of the 1T-TaS2/h-BN heterostructure on Si/SiO₂ substrate and Au electrodes labeled as source (S) and drain (D). b Current-voltage characteristics of the device under varying THz illumination intensities (0–4.1 mW/cm²), showing distinct hysteresis loops and threshold voltage shifts. Inset: equivalent circuit diagram and magnified view of threshold voltage region. c Time-dependent photocurrent response showing power-law relationship (Iph ∝ Pa) with exponent α = 0.94, as measured over increasing power densities from 0.42 to 2.5 mW/cm². d Schematic comparison of atomic arrangements in normal state versus CDW state, illustrating the periodic lattice distortion with wavelength π/kₐ in the CDW phase. e Energy-momentum diagram showing the potential energy landscape modification under applied voltage, demonstrating how CDW states are influenced by external electric fields. f The band structure undergoes changes during the I-CDW to N-CDW transition in TaS2. g Detailed current-electric field characteristics under dark and THz illumination conditions, revealing parallel shifts in I-V curves with increasing THz intensity. h Three-dimensional mapping of photocurrent as a function of temperature and electric field. i Time-resolved photocurrent waveforms at different power densities (0.1–2.5 mW/cm²). j Expanded view of rise and fall edges in the temporal response with increasing power density. k Three-dimensional mapping of frequency and voltage-dependent responsivity across different bias voltages.
