Intracavity THz generation using a thin lithium niobate plate in a compact Kerr-lens mode-locked Yb:CALGO bulk oscillator

This record contains the experimental data underlying the manuscript "Intracavity THz generation using a thin lithium niobate plate in a compact Kerr-lens mode-locked Yb:CALGO bulk oscillator". In this work, single-cycle terahertz pulses are generated by optical rectification in a 50-µm-thick MgO-doped lithium niobate plate placed inside a diode-pumped Kerr-lens mode-locked Yb:CALGO bulk oscillator operating at 85 MHz, delivering 83-fs pulses at up to 71 W of intracavity average power. The THz pulses are detected by electro-optic sampling (EOS) in a 3-mm-thick GaP crystal. Contents Laser characterization (Fig. 2 of the manuscript):- AC_withTLN.txt / AC_Without_TLN.txt — intensity autocorrelation traces of the mode-locked oscillator with and without the thin lithium niobate plate in the cavity, including sech² fits (83 fs and 82 fs). Tab-separated text with instrument header; columns: delay [ps], intensity [arb. u.], fit [arb. u.].- Spectrum_with_TLN.txt / Spectrum_Without_TLN.txt — corresponding optical spectra centered at ~1067 nm. Semicolon-separated text with instrument header (decimal comma); columns: wavelength [nm], sample, dark, and reference counts. EOS measurement, 1 Hz / 15 ps / 156 s (Fig. 3a,b):- THz_000/THz_00000.h5 — raw electro-optic sampling data (313 traces recorded in 156 s with a 1 Hz mechanical shaker over a 15-ps window). Zurich Instruments LabOne HDF5 format containing the balanced-detector signal and delay-position channels.- dark1_000/dark1_00000.h5, dark2_000/dark2_00000.h5 — dark measurements recorded with the THz beam blocked, used for noise/dynamic-range analysis and systematic correction.- parrot_thz_processing_IC_THz.ipynb — Jupyter notebook that processes the raw H5 files with the open-source package parrot (Processing All Rapidly & Reliably Obtained THz-traces; T. Vogel and C. J. Saraceno, J. Infrared Millim. Terahertz Waves 45, 967–983 (2024), https://doi.org/10.1007/s10762-024-01012-w), using the "THz + two darks" workflow. It reconstructs the averaged time-domain trace and power spectrum shown in Fig. 3a,b and the dynamic-range-versus-averaging analysis. Requirements: Python 3 with parrot, h5py, numpy, scipy, pandas, matplotlib (pip install parrot-thz or see the notebook's first cell).- Results/parrot_thz_and_two_darks_processed.h5 — processed output (averaged time-domain traces and spectra).- Results/parrot_thz_and_two_darks_light_DR_random_vs_cumulative_random_subset.csv — dynamic range versus number of averaged traces. THz power measurement (Fig. 3c):- THzPower.xlsx — THz average power versus pump diode current/power and intracavity average power. Columns: diode current [A], diode power [W], intracavity power [W], measured THz power [µW], and THz power corrected for the combined measured transmission (~14%) of the germanium plate and paper sheet used to block residual pump and second-harmonic light (20% and 76%) and the sensor head's transparent protective cover (90%). Power meter: SLT THz20, PTB-calibrated. All measurements were performed at ~70% relative humidity in an unpurged atmosphere; the THz propagation distance from generation to detection was ~50 cm.