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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on LiNbO3 by Materials Project

LiNbO3 is Calcite structured and crystallizes in the trigonal R3c space group. The structure is three-dimensional. Li1+ is bonded to six equivalent O2- atoms to form distorted LiO6 pentagonal pyramids that share corners with three equivalent NbO6 octahedra, corners with six equivalent LiO6 pentagonal pyramids, edges with three equivalent NbO6 octahedra, and a faceface with one NbO6 octahedra. The corner-sharing octahedral tilt angles are 62°. There are three shorter (2.09 Å) and three longer (2.27 Å) Li–O bond lengths. Nb5+ is bonded to six equivalent O2- atoms to form distorted NbO6 octahedra that share corners with six equivalent NbO6 octahedra, corners with three equivalent LiO6 pentagonal pyramids, edges with three equivalent LiO6 pentagonal pyramids, and a faceface with one LiO6 pentagonal pyramid. The corner-sharing octahedral tilt angles are 41°. There are three shorter (1.90 Å) and three longer (2.18 Å) Nb–O bond lengths. O2- is bonded in a distorted see-saw-like geometry to two equivalent Li1+ and two equivalent Nb5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiNbO3 by Materials Project

LiNbO3 crystallizes in the trigonal R-3c space group. The structure is three-dimensional. Li1+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All Li–O bond lengths are 2.00 Å. Nb5+ is bonded to six equivalent O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles are 37°. All Nb–O bond lengths are 2.01 Å. O2- is bonded in a 3-coordinate geometry to one Li1+ and two equivalent Nb5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiNbO3 by Materials Project

LiNbO3 is Ilmenite-like structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are ten inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 3-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.01–2.58 Å. In the second Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.05–2.36 Å. In the third Li1+ site, Li1+ is bonded in a 3-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.01–2.56 Å. In the fourth Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.07–2.37 Å. In the fifth Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.07–2.36 Å. In the sixth Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.07–2.36 Å. In the seventh Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.07–2.36 Å. In the eighth Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.06–2.40 Å. In the ninth Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.07–2.36 Å. In the tenth Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.04–2.39 Å. There are ten inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 36–41°. There are a spread of Nb–O bond distances ranging from 1.92–2.16 Å. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 34–39°. There are a spread of Nb–O bond distances ranging from 1.92–2.14 Å. In the third Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 34–40°. There are a spread of Nb–O bond distances ranging from 1.92–2.13 Å. In the fourth Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 39–40°. There are a spread of Nb–O bond distances ranging from 1.90–2.17 Å. In the fifth Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 39–40°. There are a spread of Nb–O bond distances ranging from 1.90–2.17 Å. In the sixth Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles are 40°. There are a spread of Nb–O bond distances ranging from 1.90–2.17 Å. In the seventh Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 39–40°. There are a spread of Nb–O bond distances ranging from 1.90–2.17 Å. In the eighth Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles are 40°. There are a spread of Nb–O bond distances ranging from 1.90–2.17 Å. In the ninth Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles are 40°. There are a spread of Nb–O bond distances ranging from 1.90–2.17 Å. In the tenth Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 38–41°. There are a spread of Nb–O bond distances ranging from 1.91–2.18 Å. There are thirty inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+ and two Nb5+ atoms. In the second O2- site, O2- is bonded to two Li1+ and two Nb5+ atoms to form a mixture of distorted corner and edge-sharing OLi2Nb2 trigonal pyramids. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Li1+ and two Nb5+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Li1+ and two Nb5+ atoms. In the fifth O2- site, O2- is bonded to two Li1+ and two Nb5+ atoms to form a mixture of distorted corner and edge-sharing OLi2Nb2 trigonal pyramids. In the sixth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the seventh O2- site, O2- is bonded in a 5-coordinate geometry to three Li1+ and two Nb5+ atoms. In the eighth O2- site, O2- is bonded to two Li1+ and two Nb5+ atoms to form a mixture of distorted corner and edge-sharing OLi2Nb2 trigonal pyramids. In the ninth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the tenth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the eleventh O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the twelfth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+ and two Nb5+ atoms. In the fourteenth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the fifteenth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the sixteenth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the seventeenth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the eighteenth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the nineteenth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the twentieth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the twenty-first O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the twenty-second O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the twenty-third O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the twenty-fourth O2- site, O2- is bonded in a 5-coordinate geometry to three Li1+ and two Nb5+ atoms. In the twenty-fifth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the twenty-sixth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the twenty-seventh O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the twenty-eighth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the twenty-ninth O2- site, O2- is bonded to two Li1+ and two Nb5+ atoms to form a mixture of distorted corner and edge-sharing OLi2Nb2 trigonal pyramids. In the thirtieth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiNbO3 by Materials Project

LiNbO3 is Ilmenite-like structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are eight inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded in a 3-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 1.97–2.66 Å. In the second Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.06–2.32 Å. In the third Li1+ site, Li1+ is bonded in a 3-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 1.99–2.60 Å. In the fourth Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.06–2.34 Å. In the fifth Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.06–2.33 Å. In the sixth Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.07–2.35 Å. In the seventh Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.07–2.33 Å. In the eighth Li1+ site, Li1+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Li–O bond distances ranging from 2.03–2.36 Å. There are eight inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 36–41°. There are a spread of Nb–O bond distances ranging from 1.90–2.18 Å. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 35–40°. There are a spread of Nb–O bond distances ranging from 1.91–2.15 Å. In the third Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 35–40°. There are a spread of Nb–O bond distances ranging from 1.91–2.16 Å. In the fourth Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 40–41°. There are a spread of Nb–O bond distances ranging from 1.90–2.17 Å. In the fifth Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 39–41°. There are a spread of Nb–O bond distances ranging from 1.90–2.18 Å. In the sixth Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 40–41°. There are a spread of Nb–O bond distances ranging from 1.90–2.18 Å. In the seventh Nb5+ site, Nb5+ is bonded to six O2- atoms to form distorted corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 40–41°. There are a spread of Nb–O bond distances ranging from 1.90–2.18 Å. In the eighth Nb5+ site, Nb5+ is bonded to six O2- atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedra tilt angles range from 40–41°. There are a spread of Nb–O bond distances ranging from 1.90–2.18 Å. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+ and two Nb5+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two Li1+ and two Nb5+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Li1+ and two Nb5+ atoms. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Li1+ and two Nb5+ atoms. In the fifth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the sixth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the seventh O2- site, O2- is bonded in a 5-coordinate geometry to three Li1+ and two Nb5+ atoms. In the eighth O2- site, O2- is bonded in a distorted trigonal pyramidal geometry to two Li1+ and two Nb5+ atoms. In the ninth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the tenth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the eleventh O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the twelfth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the thirteenth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Li1+ and two Nb5+ atoms. In the fourteenth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the fifteenth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the sixteenth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the seventeenth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the eighteenth O2- site, O2- is bonded in a 5-coordinate geometry to three Li1+ and two Nb5+ atoms. In the nineteenth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the twentieth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the twenty-first O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the twenty-second O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the twenty-third O2- site, O2- is bonded in a distorted trigonal pyramidal geometry to two Li1+ and two Nb5+ atoms. In the twenty-fourth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Li1+ and two Nb5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiNbO3 by Materials Project

LiNbO3 is Ilmenite-like structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are two inequivalent Li1+ sites. In the first Li1+ site, Li1+ is bonded to six O2- atoms to form distorted LiO6 octahedra that share corners with four NbO6 octahedra, edges with three equivalent LiO6 octahedra, and edges with four NbO6 octahedra. The corner-sharing octahedra tilt angles range from 10–27°. There are a spread of Li–O bond distances ranging from 2.07–2.42 Å. In the second Li1+ site, Li1+ is bonded to six O2- atoms to form distorted LiO6 octahedra that share corners with four NbO6 octahedra, edges with three equivalent LiO6 octahedra, and edges with four NbO6 octahedra. The corner-sharing octahedra tilt angles range from 10–27°. There are a spread of Li–O bond distances ranging from 2.07–2.42 Å. There are two inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with four LiO6 octahedra, edges with three equivalent NbO6 octahedra, and edges with four LiO6 octahedra. The corner-sharing octahedra tilt angles range from 10–27°. There are a spread of Nb–O bond distances ranging from 1.98–2.07 Å. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with four LiO6 octahedra, edges with three equivalent NbO6 octahedra, and edges with four LiO6 octahedra. The corner-sharing octahedra tilt angles range from 10–27°. There are a spread of Nb–O bond distances ranging from 1.98–2.07 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the second O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Li1+ and two Nb5+ atoms. In the third O2- site, O2- is bonded to two Li1+ and two Nb5+ atoms to form a mixture of distorted edge and corner-sharing OLi2Nb2 trigonal pyramids. In the fourth O2- site, O2- is bonded to two Li1+ and two Nb5+ atoms to form a mixture of distorted edge and corner-sharing OLi2Nb2 trigonal pyramids. In the fifth O2- site, O2- is bonded to two Li1+ and two Nb5+ atoms to form a mixture of distorted edge and corner-sharing OLi2Nb2 trigonal pyramids. In the sixth O2- site, O2- is bonded to two Li1+ and two Nb5+ atoms to form a mixture of distorted edge and corner-sharing OLi2Nb2 trigonal pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Three-dimensional reconstruction of THz near-fields from a LiNbO3 optical rectification source

Terahertz (THz) generation by optical rectification in LiNbO3 (LN) is a widely used technique for generating intense THz radiation. The spatiotemporal characterization of THz pulses from these sources is currently limited to far-field methods. While simulations of tilted pulse front THz generation have been published, little work has been done to measure the near-field properties of the THz source. A better understanding of the THz near-field properties will improve optimization of THz generation efficiency, transport, and coupling. We demonstrate a technique for quantitative spatiotemporal characterization of single-cycle strong-field THz pulses with 2-D near-field electro-optic imaging. We have reconstructed the full temporal 3D THz near-field and shown how the phase front can be tailored by controlling the incident pump pulse.

Gabriel, Annika↗
DOE OSTI2020

Structure Analysis of Natural Wangdaodeite—LiNbO3-Type FeTiO3

This paper reports the first structure refinement of natural wangdaodeite, LiNbO3-type FeTiO3 from the Ries impact structure. Wangdaodeite occurs together with recrystallized ilmenite clasts in shock melt veins which have experienced peak shock pressures of between 17 and 22 GPa. Comparison of natural and synthetic wangdaodeite points toward a correlation between the distortion of ferrate- and titanate-polyhedra and the c/a ratio of the unit cell. The Raman spectrum of wangdaodeite is calculated based on the refined structure. Comparison to the reported spectrum of the type-material shows that the Raman peak at 738–740 cm−1 is indicative for this phase, whereas other features in type-wangdaodeite are tentatively assigned to disordered ilmenite.

58 GEOSCIENCES↗
DOE OSTI2022

High-Quality Dry Etching of LiNbO3 Assisted by Proton Substitution through H2-Plasma Surface Treatment

The exceptional material properties of Lithium Niobate (LiNbO3) make it an excellent material platform for a wide range of RF, MEMS, phononic and photonic applications; however, nano-micro scale device concepts require high fidelity processing of LN films. Here, we reported a highly optimized processing methodology that achieves a deep etch with nearly vertical and smooth sidewalls. We demonstrated that Ti/Al/Cr stack works perfectly as a hard mask material during long plasma dry etching, where periodically pausing the etching and chemical cleaning between cycles were leveraged to avoid thermal effects and byproduct redeposition. To improve mask quality on X- and Y-cut substrates, a H2-plasma treatment was implemented to relieve surface tension by modifying the top surface atoms. Structures with etch depths as deep as 3.4 µm were obtained in our process across a range of crystallographic orientations with a smooth sidewall and perfect verticality on several crystallographic facets.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Electronic energy loss and ion velocity correlation effects in track production in swift-ion-irradiated LiNbO3: A quantitative assessment between structural damage morphology and energy deposition

The primary motivation for studying how irradiation modifies the structures and properties of solid materials involves the understanding of undesirable phenomena, including irradiation-induced degradation of components in nuclear reactors and space exploration, and beneficial applications, including material performance tailoring through ion beam modification and defect engineering. In this work, the formation mechanism of latent tracks with different damage morphologies in LiNbO 3 crystals under 0.09–6.17 MeV/u ion irradiation with an electronic energy loss from 2.6–13.2 keV/nm is analyzed by experimental characterizations and numerical calculations. Irradiation-induced damage is preliminarily evaluated via the prism coupling technique to analyze the correlation between the dark-mode spectra and energy loss profiles of irradiated regions. Under the irradiation conditions of different ion velocities and electronic energy losses, different damage morphologies, from individual spherical defects to discontinuous and continuous tracks, are experimentally characterized. During ion penetration process, the ion velocity determines the spatiotemporal distribution of deposited irradiation energy induced by electronic energy loss, meaning that the two essential factors including electronic energy loss and ion velocity co-affect the track damage. The inelastic thermal spike model is used to numerically calculate the spatiotemporal evolutions of energy deposition and the corresponding atomic temperature under different irradiation conditions, and a quantitative relationship is proposed by comparison with corresponding experimentally observed track damage morphologies. Additionally, the obtained quantitative relationship between irradiation conditions and track damage provides deep insight and guidance for understanding the damage behavior of crystal materials in extreme radiation environments and selecting irradiation parameters, including ion species and energies, for ion beam technique application in atomic-level defect manipulation, material modification, and micro/nanofabrication.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Enhancement of THz generation in LiNbO3 waveguides via multi-bounce velocity matching

Abstract To realize the full promise of terahertz polaritonics (waveguide-based terahertz field generation, interaction, and readout) as a viable spectroscopy platform, much stronger terahertz fields are needed to enable nonlinear and even robust linear terahertz measurements. We use a novel geometric approach in which the optical pump is totally internally reflected to increase the distance over which optical rectification occurs. Velocity matching is achieved by tuning the angle of internal reflection. By doing this, we are able to enhance terahertz spectral amplitude by over 10x compared to conventional single-pass terahertz generation. An analysis of the depletion mechanisms reveals that 3-photon absorption and divergence of the pump beam are the primary limiters of further enhancement. This level of enhancement is promising for enabling routine spectroscopic measurements in an integrated fashion and is made more encouraging by the prospect of further enhancement by using longer pump wavelengths.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2021

Nanocomposite‐Seeded Epitaxial Growth of Single‐Domain Lithium Niobate Thin Films for Surface Acoustic Wave Devices

Epitaxial lithium niobate (LNO) thin films are an attractive material for devices across a broad range of fields, including optics, acoustics, and electronics. These applications demand high‐quality thin films without in‐plane growth domains to reduce the optical/acoustical losses and optimize efficiency. Twin‐free single‐domain‐like growth has been achieved previously, but it requires specific growth conditions that might be hard to replicate. In this work, a versatile nanocomposite‐seeded approach is demonstrated as an effective approach to grow single‐domain epitaxial lithium niobate thin films. Films are grown through a pulsed laser deposition method and growth conditions are optimized to achieve high‐quality epitaxial film. A comprehensive microstructure characterization is performed and optical properties are measured. A piezoelectric acoustic resonator device is developed to demonstrate the future potential of the nanocomposite‐seeded approach for high‐quality LNO growth for radio frequency (RF) applications.

36 MATERIALS SCIENCE↗