AI 中文总结
研究针对传统等离子体源在近表面产生非平衡等离子体的挑战，提出定制共振场增强机制，通过微波激发规定等离子体形成位置，经理论、模拟与实验验证，建立了设计共振介电材料以控制近表面大气压等离子体的框架。
AI 中文摘要
对于传统等离子体源而言，在靠近表面处产生非平衡等离子体仍是一项重大挑战。现有的等离子体产生方案会产生空间选择性有限的体积放电，导致能量沉积效率低下以及反应中间体与附近表面之间的耦合不佳。本工作建立了定制的共振场增强机制，通过微波激发来规定等离子体在电介质表面附近形成的位置。在这种方法中，电介质材料的几何形状、折射率和堆积配置定义了共振场结构，这些结构相长干涉并局部放大电场。等离子体仅在这些共振体积内形成，其中放大的场超过局部击穿阈值，而周围气体仍低于击穿阈值。微波脉冲整形随后提供对这些模式的动态控制，可用于激发不同的共振族，确定击穿发生的位置，并重新配置微等离子体从一个脉冲到下一个脉冲所占据的位置。我们通过理论、电磁模拟以及使用一对高介电常数介质谐振器的实验来验证这一框架。这些研究识别出多个共振模式族，展示了微等离子体在规定击穿位置之间的动态重新定位，量化了每种模式的点火特性，并证实多个共振微等离子体在微波脉冲期间仍局限于局部场增强区域。总之，这些结果建立了一个用于设计共振介电材料的框架，该框架可在表面附近定位、重新配置和控制大气压等离子体。
英文摘要
Generating non-equilibrium plasmas close to surfaces remains a significant challenge for conventional plasma sources. Existing plasma generation schemes create volumetric discharges with limited spatial selectivity that lead to inefficient energy deposition and poor coupling between reactive intermediates and nearby surfaces. This work establishes tailored resonant field enhancement as a mechanism for prescribing where plasma forms near dielectric surfaces through microwave excitation. In this approach, the geometry, refractive index, and packing configuration of dielectric materials define resonant field structures that interfere constructively and amplify electric fields locally. Plasma forms only within these resonant volumes where the amplified fields exceed the local breakdown threshold, while the surrounding gas remains below breakdown. Microwave pulse shaping then provides dynamic control over these modes and can be used to excite different families of resonances, determine where breakdown occurs, and reconfigure what locations microplasmas occupy from one pulse to the next. We validate this framework through theory, electromagnetic simulations, and experiments using a pair of high-permittivity dielectric resonators. These studies identify multiple resonant mode families, demonstrate dynamic repositioning of microplasmas between prescribed breakdown sites, quantify the ignition characteristics of each mode, and confirm that multiple resonant microplasmas remain confined to localized field-enhancement regions during a microwave pulse. Together, these results establish a framework for designing resonant dielectric materials that localize, reconfigure, and control atmospheric-pressure plasmas near surfaces.
