In this work, we present first-order antisymmetric (A1) mode resonators in 128° Y-cut lithium niobate (LiNbO₃) thin films with electromechanical coupling coefficients ( $k^{2}$ ) as large as 46.4%, exceeding the state-of-the-art. The achievable $k^{2}$ of A1 in LiNbO₃ substrates of different orientations is first explored, showing X-axis direction in 128° Y-cut LiNbO₃ among the optimal combinations. Subsequently, A1 resonators with spurious mode mitigation are designed and fabricated. In addition to the large $k^{2}$ , the implemented devices show a maximum quality factor ( $Q$ ) of 598 at 3.2 GHz. Upon further optimization, the reported platform can potentially deliver a wideband acoustic-only filtering solution in 5G New Radio. [2020–0003]

中文翻译：

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具有 46.4% 机电耦合的 128° Y 切割铌酸锂 A1 谐振器

在这项工作中，我们提出了具有机电耦合系数的128° Y 切割铌酸锂 (LiNbO ₃ ) 薄膜中的一阶反对称 (A1) 模式谐振器（ $k^{2}$ ) 高达 46.4%，超过了最先进的水平。可实现的 $k^{2}$ 首先探索了不同取向的LiNbO ₃基板中 A1 的含量，显示了最佳组合中 128° Y 切割 LiNbO ₃中的X 轴方向。随后，设计和制造了具有寄生模式抑制功能的 A1 谐振器。除了大 $k^{2}$ , 实现的设备显示出最大的品质因数 ( $Q$ ) 在 3.2 GHz 时为 598。经过进一步优化，所报告的平台有可能在 5G 新无线电中提供宽带纯声学滤波解决方案。[2020-0003]