Power scalability and frequency agility of compact terahertz source based on frequency mixing from solid-state lasers

Abstract

We investigate power scalability and frequency agility of a terahertz (THz) source by mixing two frequencies generated by solid-state lasers in a nonlinear crystal. They are made possible by introducing two solid-state laser crystals sharing the same Q switch and output coupler with the same laser beams decoupled to each other by a polarizer. Following the optimization, we have improved the THz output power nearly fivefold at 1.64 THz. By replacing one of the neodymium-doped lithium yttrium fluoride crystals with a neodymium-doped yttrium aluminum garnet crystal, we have produced 2.1 μW at 2.98 THz.

Recent Progress on Compact and Portable Terahertz Source Based on Parametric Conversion from Dual-Frequency Solid-State Laser Pulses

“…This configuration is different from our previous work [30]. In this cavity, a passive Q-switch made of a 1-mm-thick Cr4+:YAG crystal with an initial transmittance of 90% (i.e.…”

“…In this section, we summary our results of introducing two laser crystals to generate two different output frequencies [30]. Our experimental result illustrates that the output powers of the solid-state lasers based on two crystals are signficantly improved.…”

Recent progress on terahertz generation based on difference frequency generation: from power scaling to compact and portable sources (Invited Paper)

“…In this section, the results of the introduction of the two laser crystals to generate two different output frequencies [30] are summarized. The experimental result illustrates that the output powers of the solid-state lasers based on the two crystals significantly improved.…”

“…This THz source can have the dimensions of 12×12×6 (inch). By introducing two Nd:YLF crystals in the laser cavity, the output power is significantly improved to 4.5 µW [30] . Such configuration allowed us to generate different THz frequencies by combining two different laser crystals [30] .…”

“…By introducing two Nd:YLF crystals in the laser cavity, the output power is significantly improved to 4.5 µW [30] . Such configuration allowed us to generate different THz frequencies by combining two different laser crystals [30] . Through further optimizations and utilization of novel configurations, the dimensions of the THz source may be reduced to 12×6×4 (inch) and eventually to the size of a laser pointer.…”