800nm Chirped Mirror HD58-50.8-12.7

Overview

The 800nm Chirped Mirror -275fs² (Ultrafast Innovations HD58) delivers mid-range negative group delay dispersion (GDD) of -275 fs² per bounce, optimized for 785nm center wavelength operation across a 690–880 nm bandwidth. This 785nm chirped mirror provides efficient GDD compensation for Ti:Sapphire oscillators, regenerative amplifiers, and OPCPA systems requiring dispersion control in the hundreds-to-thousands fs² regime without excessive bounce count.

At -275 fs² per reflection, this mirror occupies a strategic position between ultra-low-GDD pulse shapers and high-dispersion external compressors. Compensating 6000 fs² of accumulated positive dispersion requires approximately 22 bounces, making it ideal for compact CPA stretcher/compressor configurations and intracavity dispersion management where space constraints limit the number of reflections. The broadband 690–880 nm coating ensures compatibility with wavelength-tunable sources and supercontinuum generation setups.

Applications

• Ti:Sapphire CPA systems: External pulse compression and stretcher assemblies for femtosecond amplifiers operating between 750–850 nm
• Regenerative amplifier dispersion control: GVD compensation for multi-pass cavity configurations and intracavity pulse management
• OPA/OPCPA pump line optimization: Pre-compression of 800 nm pump pulses to maximize nonlinear conversion efficiency in parametric amplification
• Oscillator output compression: Fine-tuning pulse duration from mode-locked Ti:Sapphire lasers with moderate stretching from intracavity elements

Construction & Performance

Manufactured on 50.8 mm diameter × 12.7 mm thick UVFS substrate with ion beam sputtered (IBS) multilayer dielectric coating. Delivers R > 99.5% reflectance across the full 690–880 nm operational range at 7° angle of incidence (AOI) for P-polarized light. The IBS coating process ensures sub-nanometer layer thickness control critical for maintaining the designed GDD profile and minimizing higher-order dispersion ripple. LIDT rated at 0.2 J/cm² for femtosecond pulses, suitable for moderate-energy ultrafast laser systems.

Storage & Handling

Operate at 25 °C, 40–60% RH. Clean only with >99% optical-grade ethanol and lint-free lens tissue using single-pass drag method. Avoid abrasive cloths and water.