Laser properties of Fe²⁺:ZnSe fabricated by solid-state diffusion bonding

Abstract

The characteristics of an Fe 2+ :ZnSe laser at room temperature and its active elements with undoped faces were studied. Polycrystalline elements with one or two diffusion-doped internal layers were obtained by the solid-state diffusion bonding technique applied to chemical vapor deposition grown ZnSe plates preliminary doped with Fe 2+ ions in the process of hot isostatic pressing. A non-chain electric-discharge HF laser was used to pump the crystals. It was demonstrated that increasing the number of doped layers allows increasing the maximum diameter of the pump radiation spot and the pump energy without the appearance of transversal parasitic oscillation. For the two-layer-doped active element with a diameter of 20 mm an output energy of 480 mJ was achieved with 37% total efficiency with respect to the absorbed energy. The obtained results demonstrate the potential of the developed technology for fabrication of active elements by the solid-state diffusion bonding technique combined with the hot isostatic pressing treatment for efficient IR lasers based on chalcogenides doped with transition metal ions.

Single-Nanosecond-Pulse Lasing in Heavily Doped Fe:ZnSe

“…n(0) = -nt, ϕ(0) = 0 (6) where σem = 1.1•10 -18 cm 2 is the room-temperature emission cross section at a wavelength of λ = 4.5 μm, h is Planck's constant, νp is the pump radiation frequency, Ia(t) = Ip(t) [1exp [-(nt -n(t)) / 2) σabs•l)] is the absorbed pump intensity, Ip(t) is the pump intensity, c = -2L / (c • ln[R1 R2(1 -ti) 2 ]) is the photon lifetime in the laser cavity (L is the cavity length, R1 and R2 are the reflectivity of the mirrors, and ti ≈ 0.95 is cavity loss), c is the speed of light in vacuum, Va is the volume filled by the mode inside the active medium, V is the volume filled by the mode inside the cavity, l is the Fe:ZnSe crystal thickness, and ϕ0 are extra photons that are initially present in the cavity to allow laser action to start [28]. Equation 6describes the initial conditions of this system.…”

Microstructure development and optical properties of Fe:ZnSe transparent ceramics sintered by spark plasma sintering

“…14 Using the solid-state diffusion bonding technique, Fe:ZnSe laser gain with an output energy of 480 mJ and 37% total efficiency was fabricated with a laminar structure. 15 The above four methods are primarily concerned with crystalline materials. Compared to crystal materials, transparent ceramics have unique advantages which are important in the development of high performance lasers: such as easy fabrication of composite structures with different doping content, heavy and homogeneous doping of rare earth ions and fabrication of large size components.…”

Исследование пространственного распределения люминесценции в диапазоне 0.44-0.75 мкм CVD-ZnSe, легированного алюминием и железом

“…Создание эффективных источников на активных средах ZnSe : Fe 2+ связано как с развитием технологий выращивания легированных кристаллов, так и с вариацией источников возбуждения лазерной генерации. В настоящее время высокие лазерные характеристики (1.4 Дж при η slope = 52% и η abs ≈ 48%) достигнуты, например, на поликристаллических образцах ZnSe, легированных ионами железа методом диффузии [1][2][3]. В качестве источника возбуждения при этом использовался электроразрядный HF-лазер.…”