Optical bistability in an M-type atomic system

We analyze the optical bistability (OB) and absorption properties of a weak probe field in a five-level M‑type atomic system confined in a unidirectional ring cavity. We find that the threshold of OB and the absorption of the probe field in the M‑type atomic system can be controlled by adjusting the intensity and the detuning of the coupling fields. Finally, by comparison with previous results in \(\Lambda\) - and N‑type atomic systems under similar conditions, we show that the OB threshold in this case is lower than that for \(\Lambda\) - and N‑types.