A complete, non‐approximate expression of the internal impedance for an open‐ended circular cylindrical wire being subject to externally incident radiation is derived. A comparison is made with the well‐known formula given by Stratton and later given by Ramo. The modes in which the electromagnetic field oscillates are due to the incoming wave, and the corresponding boundary conditions do not lead to the homogeneous system of linear equations that produce the usual and relatively complex spectrum of damped modes discussed by Stratton. The approximations made to obtain Stratton and Ramo's formula are applicable again to the expression found here and produce the same result. Such approximations are adequate for good conductors at frequencies in the microwave region. However, it is shown that the new formulation, which includes the displacement current and the real part of the permittivity of the wire, is needed for the case of submillimeter radiation. In effect, the values of the impedance computed by using the new expression are considerably different from those resulting from Stratton or Ramo's formula in the Terahertz domain. In particular, these values show now a larger resistive part and a smaller reactive part in this domain.

中文翻译：

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外部亚毫米波照射下的圆柱线的内部阻抗

推导了暴露于外部辐射的端部开口圆柱线的内部阻抗的完整，近似值。与Stratton和后来的Ramo给出的众所周知的公式进行了比较。电磁场振荡的模式是由于入射波引起的，并且相应的边界条件不会导致线性方程的齐次系统产生由Stratton讨论的阻尼模式的通常且相对复杂的频谱。获得Stratton和Ramo公式的近似值再次适用于此处找到的表达式，并产生相同的结果。这样的近似对于在微波区域中的频率处的良好导体是足够的。然而，事实证明，新的配方，对于亚毫米辐射，需要包括位移电流和导线介电常数的实部。实际上，使用新表达式计算出的阻抗值与太赫兹域中的Stratton或Ramo公式得出的值大不相同。特别地，这些值现在在该域中显示出较大的电阻部分和较小的电抗部分。