High efficiency diode-pumped Q-switched Yb:Er:Glass lasers

Compact 0.7 mJ/11 ns eye-safe erbium laser

“…The pumping is performed at a low repetition rate (1 Hz) and the duration of a single pump pulse is about a few ms. The simplified scheme of the energy levels of Er 3+ and Yb 3+ ions is shown in figure 1 and the corresponding system of the rate equations is [10]: [10,18]; the non-radiative relaxation from the 4 I 13/2 state to the lower-lying multiplet is considered as a single depopulation channel for this state. The parameters used for the calculation are listed in table 1.…”

“…Er lasers have found their recognized applications in free-space optical communication, remote sensing (LIDAR technology), wind sensing and range-finding [2][3][4][5][6][7] in civil and military fields. The requirements for rangefinders operating at low pulse frequencies include a high pulse energy and peak power, good beam quality and low divergence, as well as a compact and robust design, preferentially with passive cooling of a laser head [7][8][9][10].…”

Spectroscopic Properties of Er3+‐Doped Na2O–La2O3–Al2O3–SiO2 Glasses

“…16 The magnitude of the magnetic dipole transition is independent of ligand fields while that of the electric dipole transition is a function of ligand fields. 17 According to Judd-Ofelt theory, the line strength of the electric dipole component in the 4 I 13/2 3 4 I 15/2 transition of Er 3ϩ is given by the following equation: 9 S ed ͓ 4 I 13/ 2 , 4 I 15/ 2 ͔ ϭ 0.0188⍀ 2 ϩ 0.01176⍀ 4 ϩ 1.4617⍀ 6 (2) Consequently, for the electric dipole 4 I 13/2 3 4 I 15/2 transition of Er 3ϩ , the ⍀ 6 parameter is dominant. It can be seen from Eq.…”

“…As a result of these investigations, some Er-doped glasses have been widely used not only as a fiber amplifier material 4 but also as a bulk laser material. 5,6 The search for more efficient laser action demands further improvements of optical, thermal, and mechanical properties of host glasses. Lanthanum aluminosilicate glasses (LAS), which have been investigated, are good glass laser hosts 7 with high glass transformation temperature, high mechanical strength, and high thermal conductivity coefficient.…”

Research of thermo-optical inhomogeneities in Yb-Er glass at diode pumping

“…Влияние тепловой линзы (ТЛ) в первую очередь сказывается на увеличе-нии расходимости выходного лазерного излучения, а другие термооптические неоднородности и вынуж-денное двулучепреломление, проявляющееся в Yb-Er активном элементе при высоких энергиях накачки, приводят к снижению эффективности генерации. В различных работах [6][7][8][9] описываются особенности работы малогабаритных неохлаждаемых лазеров на Yb-Er-стекле в условиях термооптических искаже-ний активных элементов. Очевидна необходимость их учета при расчете лазерных оптических систем, таких, например, как лазерные дальномеры с дальностью работы до нескольких десятков километров.…”