Thermo-optic phase shifters allow one to dynamically tune and control the operation of integrated-optics interferometers. They have been demonstrated nowadays in different waveguide platforms, and their reliable functioning has enabled the realization of reconfigurable circuits of notable complexity. The design approach to such devices is often based on finite-element numerical simulations, which provide accurate descriptions of the underlying thermal phenomena, at the price of long computational times. Here, on the contrary, we devise an analytical model for the heat diffusion in a simplified geometrical configuration. The model describes both static and dynamic regimes, and can be conveniently applied both to three-dimensional waveguide devices inscribed by femtosecond laser pulses and to planar lithographic circuits. The accuracy of the predictions of the model is validated with experimental measurements on Mach-Zehnder interferometers with different geometries, realized in both kinds of platforms.

中文翻译：

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热激励光波导电路的静态和动态响应的分析模型

热光移相器允许人们动态地调谐和控制集成光干涉仪的操作。如今，它们已在不同的波导平台上得到了证明，其可靠的功能使实现具有显着复杂性的可重构电路成为可能。这种设备的设计方法通常基于有限元数值模拟，该模拟以长计算时间为代价提供了对潜在热现象的准确描述。相反，在这里，我们设计了一个简化的几何结构中的热扩散分析模型。该模型描述了静态和动态状态，并且可以方便地应用于飞秒激光脉冲刻画的三维波导器件和平面光刻电路。