Ti:Sapphire Laser Crystals

Titanium - Doped Sapphire

Ti:SapphireTitanium-doped sapphire is an optically pumped, solid-state laser material with an indefinitely long stability and useful life. It is the most widely used crystal for wavelength tunable lasers. And it is a leading material in the field of femtosecond pulse lasers. Ti:sapphire laser crystals combine the excellent thermal, physical and optical properties of sapphire with the broadest tunable range of any known material. Laser output can be can be generated over the entire spectrum from 650 nm to 1100 nm. Frequency doubling the output provides tunability across the blue-green region of the visible spectrum.

Laser designers are using Ti:sapphire to generate femtosecond pulses to create new industrial tools. A properly delivered femtosecond laser pulse interacts within the target leaving the surrounding area undisturbed. Newly developed femtosecond pulsed lasers micro-machine complex fine structures in glass, metal and other materials. Active waveguides can be written below the surface, integrating optical devices within the body of a substrate. Defects in photomasks can be repaired without disturbing neighbouring patterns. And it is now possible to achieve cellular resolution in vivo for medical diagnosis with femtosecond pulse lasers.

Roditi offers Ti:sapphire laser crystals made to order, matching your precise specifications. The crystals are available in sizes from 2mm to 30mm diameter or diagonal dimension and with path length from 2mm to over 100mm long. Crystals are prepared in several standard titanium concentrations, from 0.03% to 0.25%. They are regularly available with FOM > 150, FOM > 300 and by special order with FOM > 500. (Figure of Merit is measured as the ratio of α 820 nm : α 514 nm.)

A broad absorption pump band, peaking at 490 nm: High output efficiencies, gain of 10dB/cm is typical in crystals doped at 0.1%: Broadly tunable output: Excellent conditions for frequency doubling and femtosecond pulse generation make Ti:sapphire laser crystals an excellent choice for tunable and ultra fast pulse laser systems.

Applications

  • Femtosecond Pulse Laser Material.
  • Tunable Output - 650 nm to 1100 nm.
  • Excellent Output Efficiency.

Optical and Laser Properties

Laser Action 4 Level Laser Refractive Index 1.77 at 532 nm
Output Wavelength 650 nm to 1100 nm   1.76 at 800 nm
Turnable Absorption Band 400 nm to 600 nm   1.75 at 1100 nm
Emission Cross-section Σ532nm = 4.9 x 10-20 cm2 Chemical Formula Al2O3:Ti
  Σ490nm = 6.4 x 10-20 cm2  

Absorption Coefficient

Titanium Wt% α at 532 nm
0.03% 0.60/cm ± 20%
0.05% 0.95/cm ± 20%
0.10% 1.50/cm ± 20%
0.15% 2.10/cm ± 20%
0.25% 4.10/cm ± 20%

Ti:sapphire Laser Rod Standard Fabrication Specifications

Feature Standard Special Order
Crystal Orientation A-Axis within 5°
  (E-vector parallel to C-Axis)
Diameter 4 mm to 12mm Available
Diameter Tolerance +0.0 mm/- 0.05 mm Available
Length (plano/plano) 4 mm to 150 mm Available
Length Tolerance ± 0.75 mm ± 0.50 mm
Perpendicularity of End Faces (plano/plano) 5 arc-minutes 2 arc-minutes
Parallelism of End Faces (plano/plano) 10 arc-seconds

Flatness

0.1 wave maximum 0.10 wave maximum
(plano/plano) over 90% of aperture over full aperture
Surface Finish at 5X 20-10 (scratch & dig) 10-5 (scratch & dig)
Barrel Finish 400 grit Polished approx. 80-50
End Face Bevel 0.075 mm to 0.12 mm at 45° angle
Chips No chips allowed on end face of rod; chip having maximum length of 0.3 mm permitted to lie in the area of bevel and barrel surfaces.
End Configurations plano/plano, plano/wedge, wedge/wedge or Brewster cut. Plano ends can be finished flat, concave or convex
Coatings Standard coating is BBAR with R < 5.0% each face at 532 nm and R < 0.5% each face, 650 nm to 850 nm.
Other coatings available.
FOM, α 820 mm : α 514 mm    
0.03% to 0.15% Ti FOM > 150, FOM > 300 FOM 500 and above
0.25% Ti FOM > 75, FOM > 150 FOM 300 and above