Geometrically deformed charged anisotropic models in $f(Q,T)$ gravity

In this study, we developed the geometrically deformed compact objects in the $f(Q, T)$ gravity theory under an electric field through gravitational decoupling via. minimal geometric deformation (MGD) technique for the first time. The decoupled field equations are solved via two different mimic approaches $\theta_0^0 = \rho$ and $\theta_1^1 = p_r$ through the Karmarkar condition. We conduct physical viability tests on our models and examine how decoupling parameters affect the physical qualities of objects. The obtained models are compared with the observational constraints for neutron stars PSR J1810+174, PSR J1959+2048, and PSR J2215+5135, including GW190814. Particularly, by modifying parameters $\alpha$ and $n$, we accomplish the occurrence of a "\textit{mass gap}" component. The resulting models exhibit stable, well-behaved mass profiles, regular behaviour, and no gravitational collapse, as verified by the Buchdahl--Andr\'{e}asson's limit. Furthermore, we provide a thorough physical analysis that is based on two parameters: $n$ ($f(Q,T)$--coupling parameter) and $\alpha$ (decoupling parameter). This work extends our current understanding of compact star configurations and sheds light on the behaviour of compact objects in the $f(Q,T)$ gravity.