A low-frequency 1/f conductance noise spectroscopy technique has been developed to investigate the dynamics and relaxation of charge carriers and collective modes (CDW) in quasi-1D vdW materials. The lock-in based phase-sensitive detection allows us to measure the sample noise contribution as well as background noise simultaneously. We are focusing on a few interesting problems employing the noise spectroscopy setup: (i) the dynamics of charge carriers in functionalized conductive polymers, (ii) dynamics of electric field-induced phase transitions in MoTe2 and WTe2 (iii) sliding CDW and SDW modes in quasi-1D systems and (iv) carrier’s dynamics in inorganic perovskite materials for photovoltaic applications.

1. Biswajit Das et. al., ACS Appl. Electron. Mater. (2021).

2. Arnab Bera et al, 2022 (Under preparation)

Figure 1. Lorentzian power spectra for a single τ (plotting equation (2) for τ=0.2s), (b) Power spectra from superposition of Lorentzian from equation-3. (c) Typical current fluctuation data and corresponding PSD (see ref. (17) B. Das et. al., (2021) for details). (d) Schematic diagram of the proposed experimental setup for low-frequency noise measurement based on lock-in measurements.