High-purity CVD-ZnSe polycrystal as a magneto-active medium for a multikilowatt Faraday isolator

Area of Science:

• Optics and Photonics
• Materials Science
• Solid-State Physics

Background:

• High-power Faraday isolators are crucial for protecting laser systems.
• Thermal depolarization in optical materials limits isolator performance at high laser powers.
• Chemical vapor deposition (CVD) is a key method for synthesizing optical materials like zinc selenide (ZnSe).

Purpose of the Study:

• To investigate the suitability of CVD-synthesized ZnSe polycrystals for high-power Faraday isolators.
• To evaluate the thermal depolarization performance of ZnSe-based Faraday isolators at a wavelength of 1076 nm.
• To determine the power handling capabilities of ZnSe Faraday isolators for high-power laser applications.

Main Methods:

• Synthesis of ZnSe polycrystals using the chemical vapor deposition (CVD) method.
• Fabrication of a conventional Faraday isolator using the synthesized ZnSe.
• Experimental testing of the Faraday isolator's performance under high laser power (up to 1270 W and extrapolated to 2.5 kW) at 1076 nm.
• Analysis of thermally induced depolarization as a function of laser power.

Main Results:

• No thermally induced depolarization was observed in the ZnSe Faraday isolator for laser powers up to 1270 W.
• The study experimentally indicates that thermal depolarization is not expected at laser powers up to 2.5 kW.
• CVD-synthesized ZnSe polycrystals demonstrate excellent performance as the active material in high-power Faraday isolators.

Conclusions:

• ZnSe polycrystals synthesized by CVD are highly suitable for developing high-power Faraday isolators.
• The investigated ZnSe Faraday isolator exhibits robust performance against thermal depolarization up to 2.5 kW.
• This research paves the way for more reliable and powerful optical isolator designs in high-energy laser systems.