a:
a_Delta - detuning, in units of gamma (HWHM)
a_I - \sqrt{I/I_{sat}}
a_E - entanglement E (columns = detuning, rows = intensity)

b:
column 1 - detuning, in units of gamma (HWHM)
column 2 - entanglement E

c:
column 1 - \sqrt{I/I_{sat}}
column 2 - entanglement E

d:
column 1 - \sqrt{I/I_{sat}}
column 2 - trace purity
