Tilted pulse front pumping techniques for efficient terahertz pulse generation.

Area of Science:

• Optics and Photonics
• Terahertz (THz) Science and Technology

Background:

• Optical rectification of femtosecond laser pulses is the primary method for generating single- and few-cycle THz pulses.
• The tilted pulse front pumping (TPFP) technique, developed two decades ago, has revolutionized THz source advancements.
• High-energy THz pulses are crucial for THz pump-probe experiments, material control, and future THz-driven particle accelerators.

Purpose of the Study:

• To provide a comprehensive review of the achievements in THz pulse generation using TPFP over the past two decades.
• To analyze the conventional TPFP setup, its limitations, and novel configurations for overcoming these constraints.
• To investigate the optical properties of materials used for THz generation and their suitability for TPFP.

Main Methods:

• Review of seminal achievements in TPFP for THz pulse generation.
• Analysis of conventional and novel TPFP configurations and their performance.
• In-depth spectral analysis of THz absorption, refractive index, and nonlinear coefficients in lithium niobate and semiconductors.

Main Results:

• TPFP enables efficient velocity matching in lithium niobate, crucial for high-energy THz generation.
• Adaptation of TPFP to semiconductor THz sources has led to a 200-fold increase in conversion efficiency.
• Novel TPFP configurations show promise in surmounting scaling limits for THz sources.

Conclusions:

• TPFP is a versatile and powerful technique for advancing THz pulse generation across various material platforms.
• The understanding of material optical properties is key to optimizing THz source performance.
• TPFP offers significant advantages for lithium niobate, semiconductor, organic crystal, and GaP-based THz sources.