Ca₃(TeO₃)₂(MO₄) (M = Mo, W): Mid-Infrared Nonlinear Optical Tellurates with Ultrawide Transparency Ranges and Superhigh Laser-Induced Damage Thresholds

Abstract

Intense interests in mid-infrared (MIR) nonlinear optical (NLO) crystals have erupted in recent years due to the development of optoelectronic applications ranging from remote monitoring to molecular spectroscopy. Here, two polar crystals Ca 3 (TeO 3 ) 2 (MO 4 ) (M = Mo, W) were grown from TeO 2 -MO 3 flux by high-temperature solution methods. Ca 3 (TeO 3 ) 2 (MoO 4 ) and Ca 3 (TeO 3 ) 2 (WO 4 ) are isostructural, which feature novel structures consisting of asymmetric MO 4 tetrahedra and TeO 3 trigonal pyramids. Optical characterizations show that both crystals display ultrawide transparency ranges (279 nm to 5.78 μm and 290 nm to 5.62 μm), especially high optical transmittance over 80% in the important atmospheric transparent window of 3−5 μm, and superhigh laser damage thresholds (1.63 GW/cm 2 and 1.50 GW/cm 2 ), 54.3 and 50 times larger than that of state-of-the-art MIR NLO AgGaS 2 , respectively. Notably, they exhibit the widest band gaps and the loftiest laser-induced threshold damages among the reported tellurates so far. Moreover, Ca 3 (TeO 3 ) 2 (MO 4 ) exhibit type I phase matching at two working wavelengths owing to their large birefringence and strong secondharmonic generation responses from the distorted anions, as further elucidated by the first-principles calculations. The above characteristics indicate that Ca 3 (TeO 3 ) 2 (MO 4 ) crystals are high-performance MIR NLO materials, especially applying in high-power MIR laser operations.

Shedding Light on the Structure and Characterization of K2ZnGe2O6: A Phase-Matchable Nonlinear Optical Crystal

“…exhibiting high polar displacement in the coordination environment . According to the diverse strategies, a variety of potential inorganic NLO crystals including borates, − phosphates, − and molybdate oxides − were widely investigated. Despite these identified achievements, most of them are focused on optical applications in the UV–vis–near-infrared (NIR) regions.…”

Recent advances in tellurite molybdate/tungstate crystals

“…Ni 3 (MoO 4 )(TeO 3 ) 2 , 36 Co 3 (Mo 2 O 8 )(TeO 3 ), 37 Bi 2 Te 2 W 3 O 16 , 38 Na 2 -MTe 4 O 12 (M = W, Mo), 39 Cd 3 Te 2 Mo 6 O 10 and Ca 3 (TeO 3 ) 2 (MO 4 ) (M = Mo, W). 40,41 Most of these compounds are synthesized using a conventional high-temperature solid state reaction method. In addition, owing to their non-centrosymmetric structures, the powder SHG measurements of these compounds are usually performed using 1064 nm radiation with a Kurtz-NLO system.…”

“…Based on the SOJT theory, a series of tellurite molybdate/tungstate compounds have been developed by Halas Yamani's research group, Jacobson's research group, Tao's group, Mao's group, Xia's group and Shen's group, such as AMM ′ 2 O 9 (A = K, Rb, Ba, Na, M = Te, Nb, Ta, M′ = Mo, W), 19,20 A 2 TeW 3 O 12 (A = K, Rb, or Cs), 21 MTeMoO 6 (M = Mn, Zn, Cd, Mg, Co), 22–27 Na 2 Te 3 Mo 3 O 16 , 28 Na 6 Te 4 Mo 6 O 29 , 29 Zn 2 MoO 4 TeO 3 , 30 (NH 4 ) 2 Te 2 WO 8 , 31 (NH 4 ) 2 Mo 3 TeO 12 , 32 Ag–Mo/W–Te–O, 33 Hg 2 MoTeO 6 , 34 Hg 2 Mo 2 TeO 9 , 34 Ni 3 (Mo 2 O 8 )(TeO 3 ), 35 Ni 3 (MoO 4 )(TeO 3 ) 2 , 36 Co 3 (Mo 2 O 8 )(TeO 3 ), 37 Bi 2 Te 2 W 3 O 16 , 38 Na 2 MTe 4 O 12 (M = W, Mo), 39 Cd 3 Te 2 Mo 6 O 10 and Ca 3 (TeO 3 ) 2 (MO 4 ) (M = Mo, W). 40,41 Most of these compounds are synthesized using a conventional high-temperature solid state reaction method. In addition, owing to their non-centrosymmetric structures, the powder SHG measurements of these compounds are usually performed using 1064 nm radiation with a Kurtz-NLO system.…”

“…The crystal growth of β-BTM was first developed by Tao's group in 2008. 49 Since then, the crystal growths of β-BTW, α-BTW, α-BTM, MTM, CsTM, and CsTW by Tao's group, 24,43,45,48,50,51 NTW by Halasyamani's group, 52 Na 2 Te 3 Mo 3 O 16 by Shen's group, 53 CdTM and ZnTeMoO 6 by Hong's group, 26,27 Ca 3 Te 2 MoO 10 and Ca 3 Te 2 WO 10 by Xia's group, 41 and CoTeMoO 6 and MnTeMoO 6 at Yibin University have been successively reported. 54,55 With the optimization of crystal growth parameters, large-sized and high-quality crystals were successively obtained by our group.…”

Growth and Characterization of a Nonlinear Optical Crystal Cd3Te2WO10 Decorated by WO4 Tetrahedra Showing a Large Band Gap

“…Molybdenum/tungsten tellurates with the two groups, SALP Te 4+ and d 0 Mo 6+ /W 6+ cations, play a vital role among numerous SHG NLO crystals. To date, molybdenum/tungsten tellurates with excellent NLO performances have been intensively explored and grown in bulk crystals such as BaTe 2 MO 9 (M = Mo, W), Cs 2 TeM 3 O 12 (M = Mo, W), , ATeMoO 6 (A = Mg, Zn, Cd, Mn, Co), − etc. − Most of them not only possess good growth habit, great SHG intensity, moderate band gap ( E g ), and wide transparent range covering the midinfrared (MIR) beam source spanning 3–5 μm, one of the important atmospheric transparent windows which has shown splendid application prospects in the military, industry, and academic research fields, , but also exhibit very promising Raman and electroelastic performance at room temperature. Furthermore, a number of compounds having wide transparent and high laser-induced damage threshold (LIDT) are expedient to the high-power output utilizing a MIR beam source.…”