Scanning-Free Solid-State Biased THz Waveform Detection from 1 to 30 THz

Recent advancements in high-energy terahertz (THz) sources, driven by powerful laser systems, now enable the generation of ultrashort THz pulses with energies up to several millijoules, spanning frequencies from 1 to 30 THz. A key breakthrough is developing a reliable single-shot detection method, essential for measuring the electric field of these broadband, low-repetition-rate pulses, which is vital for exploring the complex dynamics of THz emission and studying extreme nonlinear material responses in this range. Existing detection methods have been limited to lower frequencies. Here, we introduce the first potentially single-shot-capable THz detection technique for capturing ultra-broadband waveforms. Utilizing a 1-μm-thick SiN detection chip, we exploit THz field-induced second harmonic generation to achieve real-time monitoring of THz waveforms with frequency content up to 30 THz. By adjusting the angle between the THz and optical probe beams, we can fine-tune the detection window for enhanced flexibility. Our novel THz detector is ideally suited for high-energy, low-repetition-rate sources, unlocking new frontiers in THz research.