Cr:ZnSe – Chromium doped zinc selenide
Absorption range 1450 nm – 2100 nm | Emission range 1900 nm – 3300 nm
Chromium zinc selenide (Cr2+:ZnSe) exhibits high absorption coefficient and can be very efficiently pumped over broad 1450-2100 nm range of various sources or used as passive Q-switch in this range.
Cr:ZnSe is tunable and it lases at wide wavelength range from 1900 nm to 3300 nm. Probably biggest disadvantage of chromium zinc selenide crystal is strong thermal lensing effect which creates power limits.
Unlike usually found in the market poly-crystalline form, 3photon Cr:ZnSe is mono-crystalline.
- Large absorption coefficient;
- Structure: cubic;
- Sizes: up to 40 x 40 x 50 mm;
- Emission range of 1.9 – 3.3 µm;
- Extensive gain bandwidth > 500 nm;
- Lifetime of excited state (300 K) is approximately ~5.5 µs;
- Efficient performance at room temperature;
- Available density number concentrations up to 1020 cm-3.
- As a gain material in compact laser systems;
- As passive Q-switch for 1450-2100 nm lasers;
- Source for pumping middle infrared (MIR) optical parametric oscillators (OPO);
- Infrared (IR) missile countermeasure systems (ship and aircraft based);
- Free space communications;
- Gas tracing and analysis;
- Chemical warfare detection;
- Non-invasive medical diagnostics;
- Medical surgeries;
- Cavity ring down (CRD) spectroscopy.
In the market most common Cr:ZnSe growing technology is Chemical Vapor Deposition (CVD)
However, 3photon Cr:ZnSe is grown via :
a) high pressure vertical Bridgman (HPVB) method.
b) High pressure vertical zone melting method.