Coexistence of antiferromagnetism and glassy magnetic state and signature of quantum interference effects in the frustrated ternary silicides HoScSi and ErScSi

Determining the fundamental mechanisms that are responsible for the observed anomalies in electrical transport is a key objective in condensed matter physics. Among these, quantum interference effects such as electron-electron (e-e) interaction and weak localization (WL) effects play an important role in determining the low-temperature ($T$) electrical transport behavior in disordered systems. Here, we provide experimental evidence for the observation of quantum interference effects driven low-temperature resistivity (ρ) minima in HoScSi and ErScSi. Temperature dependent magnetic and neutron diffraction studies clearly establish that HoScSi undergoes a transition from a paramagnetic to a commensurate antiferromagnetic (AFM) state near $T_{1\mathrm{Ho}}\sim 57$ K, which decreases to 28 K ($T_{1\mathrm{Er}}$) in ErScSi. Furthermore, in HoScSi, an incommensurate AFM state is observed below ∼35 K. Additionally, cluster glass phases are also noted in both intermetallics at lower $T$, which coexist with the antiferromagnetic state. These observed features have been attributed to the presence of ferromagnetic (FM) and AFM exchange interactions. In addition to this, ρ minima are noted near 20 K ($T_{\mathrm{minHo}}$) and 18 K ($T_{\mathrm{minEr}}$) in HoScSi and ErScSi, respectively. The systematic analysis of the magnetic field and $T$ dependence of ρ indicates that the observed anomaly originates from a disorder-enhanced e-e interaction and the WL effect.