Superior infrared nonlinear optical (NLO) crystals are in urgent demand in the development of lasers and optical technologies for communications and computing. The critical challenge is to find a crystal with large non‐resonant phase‐matchable NLO coefficients and high laser damage threshold (LDTs) simultaneously, which however scale inversely. This work reports such a material, MgSiP2,that exhibits a large second harmonic generation (SHG) coefficient of
Nonlinear optical (NLO) crystals with superior properties are significant for advancing laser technologies and applications. Introducing rare earth metals to borates is a promising and effective way to modify the electronic structure of a crystal to improve its optical properties in the visible and ultraviolet range. In this work, we computationally discover inversion symmetry breaking in EuBa3(B3O6)3, which was previously identified as centric, and demonstrate noncentrosymmetry via synthesizing single crystals for the first time by the floating zone method. We determine the correct space group to be
- NSF-PAR ID:
- 10472877
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optical Materials Express
- Volume:
- 13
- Issue:
- 12
- ISSN:
- 2159-3930
- Format(s):
- Medium: X Size: Article No. 3416
- Size(s):
- ["Article No. 3416"]
- Sponsoring Org:
- National Science Foundation
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Abstract d 14≈d 36= 89 ± 5 pm V−1at 1550 nm fundamental wavelength, surpassing the commercial NLO crystals AgGaS2, AgGaSe2, and ZnGeP2. First principles theory reveals the polarizability and geometric arrangement of the [SiP4] tetrahedral units as the origin of this large nonlinear response. Remarkably, it also exhibits a high LDT value of 684 GW cm−2, which is six times larger than ZnGeP2and three times larger than CdSiP2. It has a wide transparency window of 0.53–10.35 µm, allowing broadband tunability. Further, it is Type I and Type II phase‐matchable with large effective SHG coefficients ofd eff,I≈80.2 pm V−1andd eff,II≈73.4 pm V−1. The outstanding properties of MgSiP2make it a highly attractive candidate for optical frequency conversion in the infrared. -
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Abstract Calcium germanides with two mid‐late rare‐earth metals, Ca5−
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