Induced transparency and absorption effects are observed in the throughput of a hollow bottle microresonator using
either mode coupling or superposition of two coresonant orthogonally polarized whispering gallery modes of very
different quality factors (Q). The first method is based on intracavity cross polarization coupling when either the TE
mode or the TM mode is driven, resulting in coupled mode induced transparency (CMIT) and coupled mode induced
absorption (CMIA). The second method is based on superposition of the throughputs when the two modes are
simultaneously driven by input light linearly polarized at an angle of 45° with respect to the TE-TM basis of the
resonator, and throughput of the same polarization is detected. In this way, superposition can be created even in the
absence of cross polarization coupling. The observations using the second method are referred to as coresonant
polarization induced transparency and absorption (CPIT, CPIA). Coresonance between the TE and TM modes can be
obtained by strain tuning. The above behaviors are analogous to electromagnetically induced transparency and
absorption (EIT, EIA), and enable slow light and fast light, i.e., the delay or advancement of an incident resonant pulse.
Experimental results representative of several different types of behavior are presented here. Induced transparency is
seen to be accompanied by pulse delay, whereas induced absorption can be accompanied by pulse advancement or delay.
The results are analyzed and explained by simple analytical modeling and by comparison to the output of a more detailed
numerical model describing these effects.