# Single-cycle scalable terahertz pulse source in refleciton geometry

## TL;DR

This paper proposes a simple, scalable, and efficient single-cycle terahertz pulse source using a tilted-pulse-front technique in reflection geometry, enabling high-field THz pulses for advanced accelerator applications.

## Contribution

It introduces a novel, compact, and energy-scalable THz source design with a reflective grating in a single crystal slab, achieving high field strengths and symmetric beam profiles.

## Key findings

- Predicted 50 MV/cm focused field with 5.6 mJ pulse energy.
- Achieved generation of high-energy, single-cycle THz pulses.
- Demonstrated potential for THz-driven particle accelerators.

## Abstract

A tilted-pulse-front pumped terahertz pulse source is proposed for the generation of extremely high field single-cycle terahertz pulses. The very simple and compact source consists of a single crystal slab having a blazed reflection grating grooved in its back surface. Its further important advantages are the energy scalability and the symmetric THz beam profile. Generation of 50 MV/cm focused field with 5.6 mJ terahertz pulse energy is predicted for a 5 cm diameter LiNbO$_3$ crystal, if the pump pulse is of 450 mJ energy, 1030 nm central wavelength and 1 ps pulse duration. Such sources can basically promote the realization of THz driven electron and proton accelerators and open the way for a new generation concept of terahertz pulses having extreme high field.