= Solution
For an isolated easy-axis <ferromagnet> undergoing coherent reversal, the ideal low-temperature loop is approximately rectangular, switching between $\pm M_s$ at $\pm H_c$. It has remanent <Magnetization> and a large response near switching. An ideal compensated <antiferromagnet> has essentially no <remanence> and a small, approximately reversible linear net <Magnetization> $M=\chi_{\rm AF}H$ at fields far below its exchange/spin-flop scales. Strong antiferromagnetic exchange makes substantial canting costly, so its low-field <magnetic susceptibility> is small relative to the <ferromagnet>'s unsaturated switching response.
This comparison does not say the <ferromagnet> has a larger differential slope at every field: on its saturated branches $dM/dH$ can also be small. Nor does it rule out spin-flop transitions at much larger fields, outside the sketched range. The original plot uses arbitrary normalized scales.
\Image[/past-exam-of-the-mphil-in-micro-and-nanotechnology-enterprise-course-of-the-university-of-cambridge/2021/paper-2-exchange-bias.png]
{title=Original isolated-ferromagnet and antiferromagnet responses, and a field-cooled shifted bilayer loop}
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