Theory and application of complex geometric optics in inhomogeneous magnetized plasmas

A new treatment is presented of geometric optics in inhomogeneous magnetized plasmas with non‐Hermitian dielectric tensors. Previous treatments assume either that the dielectric tensor is nearly Hermitian or that the frequency is nearly real. This is done in order to restrict the values of space‐time coordinates along a ray to real values. This work eliminates this restriction and gives a new interpretation of the meaning of complex‐valued coordinates, and shows that it extends the range of validity of the theory. This derivation is fully covariant, eliminating the special role played by the time in previous derivations. A new numerical treatment of the amplitude equation, which may be more convenient than ray tracing, is suggested. An application of the method of complex ray tracing to lower hybrid wave propagation in a tokamak is introduced.