1：Experimental Design and Method Selection

A THz-TDS system uses a femtosecond Yb-doped photonic crystal ?ber ampli?er as the pump source. The THz wave emitter is a 3 mm ?1 1 0?-cut GaP crystal. The output power and the waveform of the emitted THz wave are characterized by a Golay cell and the standard THz-TDS, respectively.

2：Sample Selection and Data Sources

Four kinds of EO materials were prepared, including ZnTe and GaP crystals, DAST wafer and GaSe ?lm.

3：List of Experimental Equipment and Materials

Golay cell (GC-1P, TYDEX), spectrometer (YOKOGAWA AQ6370B), femtosecond Yb-doped photonic crystal ?ber ampli?er.

4：Experimental Procedures and Operational Workflow

The generated THz radiation is collected and focused onto the samples with four 90° o?-axis parabolic mirrors for EOS to characterize the modulated amplitude and phase of the THz wave. Part of the probe beam is imported into a spectrometer to measure the spectral intensity change caused by THz wave.

5：Data Analysis Methods

The EO coe?cients are calculated based on the spectral intensity modulation and compared with literature data.