We report a neutron diffraction study using epithermal neutrons to probe the origin of negative magnetization (NM) and its correlation with exchange bias and electronic transport in $\mathrm{G}{\mathrm{d}}_2\mathrm{CoRu}{\mathrm{O}}_6$. This double perovskite crystallizes in the monoclinic $P{2}_1/\mathrm{n}$ space group and exhibits magnetic ordering at $T_{\mathrm{C}}\approx 51$ K. Magnetization measurements reveal NM below the compensation temperature ($T_{\mathrm{comp}}\approx 11$ K), which shifts to lower temperatures with increasing magnetic field and vanishes for $H$ ≥ 500 Oe. Low temperature (6 K) neutron diffraction study shows that $\mathrm{C}{\mathrm{o}}^{2+}$ and $\mathrm{R}{\mathrm{u}}^{4+}$ sublattices undergo a canted antiferromagnetic type ordering with antiferromagnetic spin alignment along the $c$ axis and a ferromagnetic component along the $b$ axis, while no ordered magnetic moment is detected for ${\mathrm{Gd}}^{3+}$ ions. Specific heat exhibits a sharp λ-anomaly at 3.5 K, confirming the long-range magnetic ordering of ${\mathrm{Gd}}^{3+}$ sublattice. The observed NM behavior in $M$($T$) curves is explained by polarization of ${\mathrm{Gd}}^{3+}$ moments induced by the internal field from the canted Co/Ru sublattice, consistent with Cooke's model. A detailed examination of field-cooled $M$ vs $H$ curves reveals the presence of exchange bias and its sign reversal around the $T_{\mathrm{comp}}$ in the sample. Interestingly, exchange-bias magnitude depends on the maximum field applied during the hysteresis measurements. Furthermore, the coercivity and remnant magnetization values, derived from the $M$($H$) curves, exhibit a minimum around $T_{\mathrm{comp}}$. Electrical resistivity follows a semiconducting variable-range hopping model below 100 K, with a sharp increase below 50 K coinciding with $T_{\mathrm{C}}$, indicating a strong coupling between structural distortions, magnetic interactions, and charge localization. These findings reveal an intricate coupling of structural, magnetic, and electronic degrees of freedom in $\mathrm{G}{\mathrm{d}}_2\mathrm{CoRu}{\mathrm{O}}_6$, highlighting its potential for spintronic and magnetic device applications where tunable compensation and exchange bias effects and their intertwined behavior are desirable.

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• Electrical properties
• Magnetic order
• Magnetic susceptibility
• Magnetism
• Magnetic techniques
• Magnetization measurements
• Neutron diffraction
• Susceptibility measurements
• X-ray diffraction