800nm Chirped Mirror CM1483-25.4-6.35

Overview

The 800nm Chirped Mirror -65fs² (Ultrafast Innovations CM1483) delivers moderate negative group delay dispersion (GDD) of -65 fs² per bounce at 775nm center wavelength, optimized for Ti:Sapphire oscillator cavities and CPA systems requiring precise sub-100 fs pulse compression. This 775nm chirped mirror provides GDD compensation across the 650–900 nm spectral range with >99.7% broadband reflectance, making it ideal for intracavity dispersion control in mode-locked lasers and multi-pass compressor stages.

The -65 fs² GDD value positions this chirped mirror as a workhorse component for standard Ti:Sapphire systems, where approximately 15–25 bounces provide dispersion compensation for typical cavity optics and gain media. Unlike ultra-low GDD mirrors requiring numerous reflections or high-GDD mirrors with limited bandwidth, this moderate GDD enables compact compressor geometries while maintaining broad spectral coverage essential for sub-30 fs pulse generation.

Applications

• Ti:Sapphire oscillator intracavity dispersion management: 6–12 bounces compensate for positive GDD from gain crystal and output couplers in mode-locked laser cavities
• Chirped pulse amplification (CPA) pre-compression: Multi-bounce configurations fine-tune spectral phase before Ti:Sapphire regenerative or multipass amplifiers
• OPCPA pump line dispersion control: Manages temporal broadening of 800 nm pump pulses in optical parametric chirped pulse amplification systems
• Two-photon microscopy pulse optimization: External compressor for delivering transform-limited 80–100 fs pulses at tissue target planes

Construction & Performance

Manufactured on 25.4 mm diameter × 6.35 mm thick UV-fused silica (UVFS) substrates with ion beam sputtered (IBS) multilayer dielectric coatings. The design delivers R>99.7% reflectance from 650–900 nm at 0° angle of incidence for P-polarization. GDD remains stable at -65 ± 10 fs² across the 750–800 nm range. The precision IBS coating ensures <0.5% GDD oscillation for minimal higher-order dispersion, critical for maintaining pulse fidelity in ultrafast laser systems. LIDT specification of 0.2 J/cm² supports operation with focused femtosecond pulses in amplifier beam paths.

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.