Executive Summary : | Magnetic materials contain unpaired electrons carrying the magnetic moment, which interacts with each other to create a variety of magnetic phenomena. In frustrated magnets, all magnetic interactions are not simultaneously satisfied, leading to various magnetic phases. The quantum spin liquid (QSL) state is more interesting due to its potential applications for topological quantum computation. In recent years, a subclass of QSLs, known as Kitaev QSLs (KQSLs), has gained attention. The Kitaev honeycomb model is a classic example of QSL, hosting a range of gapped and gapless QSL phases and nonabelian anyons. The Kitaev interaction was initially thought to be artificial but later revealed that it is the dominant spin interactions in few transition metal oxides, where spin-orbit coupling plays a major role. The α-RuCl₃ is an extensively studied material due to its close realization of the Kitaev model. The Kitaev interactions are the strongest magnetic interaction in this system, but other interactions also lead to a magnetically ordered state at TN = 7.5 K. The honeycomb layered cobaltates (A₃Co₂SbO₆, A= Na, Li, Ag, Na₂Co₂TeO₆) were recently anticipated to be capable candidates for achieving the KQSL state. The project aims to engineer the J3 exchange parameter by gradually substituting Te6+ and Sb5+ ions with magnetic and nonmagnetic ions to achieve the disorder magnetic ground state, or spin-liquid state. The study will compare the two major lattice engineering parameters, M –L–M angle and interatomic distances, to better understand exchange paths and control them to achieve the KQSL state. |