High-order stimulated Raman scattering and cascaded nonlinear lasing effects in crystals of (χ⁽³⁾→ χ⁽²⁾)-active orthorhombic PbB₄O₇

Abstract

High-order stimulated Raman scattering (SRS) and cascaded χ (3) → χ (2) generation effects in new nonlinearlaser crystals of PbB 4 O 7 were observed with picosecond laser pumping. All registered χ (3) -and χ (2) -lasing components in the visible and near-IR were identified and attributed to the SRSpromoting mode ωSRS ≈ 148 cm −1 of the studied crystal.Example of a grown crystal of PbB4O7, together with two crystal samples that were cut from the bulk of the crystal

Monoclinic LaBO2MoO4:Nd3+- a new SE- and (χ(2)+χ(3))-active crystal for multifunctional lasers

“…g) Self-FT (SFM-SE) is the self-frequency-tripling, i.e., cascaded summing parametric lasing involving the frequency of the SE and its SHG of Nd 3+ lasants [12]. In continuation of our investigations of nonlinearlaser borates (undoped BiB 3 O 6 [4], LiGeBO 4 [5], [7], PbB 4 O 7 [8]), recently we reported a new nonlinear optical crystal, lanthanum borate molybdate, LaBO 2 MoO 4 [9], which turned out to be an effective material for many-phonon generation via stimulated Raman scattering (SRS), producing a Stokes and anti-Stokes lasing comb in the visible and near IR wavelength region. In addition to this, second harmonic generation (SHG) and cascaded χ (3) ↔ χ (2) processes were detected.…”

Observation of many-phonon stimulated Raman scattering and related cascaded nonlinear-laser effects in monoclinic LaBO2MoO4 single crystals

“…Therefore, the search and characterization of new molybdate or borate crystals is of current interest. Regarding the broad usability of borates and molyb- [7,8] ≈ 888, ≈ 320 [12] ≈ 925, ≈ 310 [19] ≈ 532 [22,23] [24,25] [4,22,26] [27] ≈ 148 …”

Polarized Raman and IR spectra of non‐centrosymmetric PbB4O7 single crystal

“…6 Since the absence of any bands above 1250 cm 1 precludes the presence of BO 3 units in the PbB 4 O 7 structure, the spectra can be subdivided into separate regions in which the typical vibrations of the tetrahedral BO 4 system are observed. On the basis of previous studies of a number of borates, we can conclude that the asymmetric stretching modes as BO 4 3 appear in the range 900-1200 cm 1 , in the range 400-440 cm 1 and the symmetric bending modes υ s BO 4 2 in the range 280-360 cm 1 (Figs 1-3 and Table 1). 9 -15 Apart from the above-described vibrations, the modes of the bridge -BOBOB-network could also be identified in the Raman and IR spectra.…”

“…1 They are chemically and mechanically very stable, with good transparency down to the deep UV region. 2,3 Recently, lead tetraborate (PbB 4 O 7 ) has been discovered as a prospective Raman laser, 4 in spite of its poor second harmonic response (SHG), very small birefringence and absence of angle phase matching. 1,5 The structure of PbB 4 O 7 has been reported.…”