Fig. 3: Reconfigurable photoelectric logic characteristic of the 1T-TaS₂ device.

a The 1T-TaS₂ device functions as a logic device, considering both bias voltage and THz input as two inputs to achieve logical functionality. b IV characteristics driven by a current source at low temperature (77 K) with five sequential scanning times. c The effect of different power THz light on the phase transition bias point at low temperature (77 K). d–f Truth table of the logic functions implemented by the device under different bias waveforms. Truth tables for the 1T-TaS₂ device in three operational modes (C→F, D→F, and B→E). “Light density” denotes THz radiation intensity (00, 01, 10 correspond to 0, 2.1, and 4.1 mW/cm² in Fig. 4c). Vds represents the bias voltage (0 for lower voltage points C, D, B; 1 for higher voltage points F, E). “Last” indicates the initial resistance state (0 for HRS, NC-CDW phase; 1 for LRS, IC-CDW phase). “Out” is the resulting state based on the logic operations. g–i Schematic diagram of the logic function implemented by the device under different bias conditions. g illustrates the C→F logic operation with THz input and voltage control V_ds, incorporating “and” and “or” gates with a state transition mechanism. h shows the simplified D→F configuration where the device implements a different logical pathway with “and” and “or” gates. i depicts the B→E operation with THz input and V_ds control.