Time-Resolved Millimeter-Wave Conductance of Bismuth Oxy-Sulfide (Bi₂O₂S) Thin Films with and Without External Magnetic Field
Description
This dataset provides time-resolved millimeter-wave conductance (TRmmWC) measurements of Bismuth Oxy-Sulfide (Bi₂O₂S) thin films acquired under zero magnetic field and finite (low) applied magnetic field conditions (about 200 Gauss). The data were obtained using a contact-free optical pump – a 0.67ns width optical (pump) excitation from a 532nm laser pulsed at 1 kHz, and a continuous wave millimeter-wave probe beam (at 120 GHz). The averaged transients obtained by a digital storage oscilloscope (DSO) were saved as .csv files labeled as Upon pulsed optical excitation with a fluence of 10.6 micro-Joules per square cm, excess carriers are generated in the Bi₂O₂S films, and the resulting transient changes in millimeter-wave transmission (or voltage) are recorded as a function of time. Measurements performed in the absence of a magnetic field establish the baseline carrier transport behavior. In contrast, measurements with an applied magnetic field enable investigation of magneto-conductive effects, scattering mechanisms, and potential localization phenomena. The dataset is intended for reuse by the broader research community working on: • Magneto-transport and magnetoresistance effects • Disorder- and localization-driven transport phenomena • Drude and Drude–Smith conductivity modeling • Benchmarking and validation of TRmmWC / THz–mm-wave experimental techniques All data are provided in a .CSV format (time, Voltage) suitable for analysis using MATLAB, Python, or equivalent scientific software environments. Background noise has already been subtracted from the attached data for the one with magnet and the other no-magnet case. The voltages must be divided by 35.7 which is the low noise amplifier (LNA) gain of the system. Data Contents The dataset includes: • Time-resolved millimeter-wave transients recorded following optical excitation • Measurements acquired without magnetic field • Measurements acquired with applied magnetic field Recommended References 1. Roy, B., Jones, Charles R. Jones, B. Vlahovic, Harald W. Ade, and Marvin H. Wu, A time-resolved millimeter wave conductivity (TR-mmWC) apparatus for charge dynamical properties of semiconductors, Rev. Sci. Instrum., Vol. 89 104704 (2018). 2. Ulbricht, R., Hendry, E., Shan, J., Heinz, T. F., & Bonn, M. Carrier dynamics in semiconductors studied with time-resolved terahertz spectroscopy. Reviews of Modern Physics, 83, 543–586 (2011). 3. Chitara, B., Amit K. Shringi, Biswadev Roy, Marvin H. Wu, and Fei Yan, Facile synthesis and morphology-induced photoconductivity modulation of Bi2O2S nanosctructures, Materials Letters, 346 134545 (2023).
Files
Steps to reproduce
Follow the "Experimental Section" of the reference paper Chitara et al. (2023), and experiment as described in Roy et al. (2018) using a 200G permanent magnet