MgSiP2: An Infrared Nonlinear Optical Crystal with a Large Non‐Resonant Phase‐Matchable Second Harmonic Coefficient and High Laser Damage Threshold

Abstract

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 d14≈d36 = 89 ± 5 pm V−1 at 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 ZnGeP2 and 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 of deff,I ≈80.2 pm V−1 and deff,II ≈73.4 pm V−1. The outstanding properties of MgSiP2 make it a highly attractive candidate for optical frequency conversion in the infrared.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jul 14, 2023
Source ID
10.1002/adom.202301060

Entities

People

  • Gian‐marco Rignanese
  • Guillaume Brunin
  • Jingyang He
  • Ke Wang
  • Robert Robinson
  • Rui Zu
  • Seng Huat Lee
  • Suguru Yoshida
  • Venkatraman Gopalan
  • Victor Trinquet
  • Yanglin Zhu
  • Yingdong Guan
  • Yu Wang
  • Zhiqiang Mao

Organizations

  • Air Force Office of Scientific Research
  • National Science Foundation
  • Northwestern Polytechnical University
  • Pennsylvania State University
  • UCLouvain
  • United States Department of Energy

Tags

Fields of Study

  • Physics

Readers

  • Materials Science and Engineering.
  • Optical Physics and Photonics.

Technology Areas

  • Directed Energy
  • Directed Energy - Lasers