How does total internal reflection from non-planar surfaces in an NPRO help eliminating standing wave and why a planar structure can't give the same result? I understand that to produce optical diode we need three components
- non-reciprocal rotation (Faraday rotation due to magnetic field)
- reciprocal rotation (waveplate)
- Polarizer (dichroic OPC)
How the system as a whole works as a travelling wave ring oscillator ?