Figure 1

Sample characteristics and measurement set-up. (a) Crystal structure of 1T-TaS₂ (upper schematic) and Bi-2212 (lower schematic) viewed along the direction parallel to the ab-plane. (b) Schematic of monolayer 1T-TaS₂ along the c-axis in CCDW state. The interlocked clusters of Ta atoms (“star of David”) are sketched in dark yellow for the Ta atoms and the chemical bonds between Ta atoms, excluding the central one, are sketched in black. The S atoms are not shown. (c) Atomic force microscope (AFM) images of the cleaved surfaces for thin flakes of Bi-2212 (left) and 1T-TaS₂ (right). The scale bar corresponds to 1 μm. The surface mean roughness of thin flake Bi-2212 and 1T-TaS₂ are 1.55 Å and 1.52 Å respectively. (d) Schematic depicting experimental set-up for making four-terminal current-voltage and differential conductance vs voltage measurements using an AC + DC adder in conjunction with one DC voltmeter and two synchronized lock-in amplifiers, one for AC current and the other for AC voltage. Inset: photograph of Bi-2212/1T-TaS₂ device. The scale bar corresponds to 1 mm.