Isoelectronic tuning of heavy fermion systems: Proposal to synthesize Ce 3 Sb 4 Pd 3

摘要: The study of (quantum) phase transitions in heavy fermion compounds relies on a detailed understanding the microscopic control parameters that induce them. While influence external pressure is rather straightforward, atomic substitutions are more involved. Nonetheless, replacing an elemental constituent compound with isovalent atom is, effects disorder aside, often viewed as merely affecting lattice constant. Based this picture chemical pressure, unit-cell volume identified empirical proxy for Kondo coupling. Here, instead, we propose ``orbital scenario'' which coupling complex systems can be tuned by isoelectronic little or no effect onto cohesive properties. Starting insulator ${\mathrm{Ce}}_{3}{\mathrm{Bi}}_{4}{\mathrm{Pt}}_{3}$, consider, within band theory, pnictogen ($\mathrm{Bi}\ensuremath{\rightarrow}\mathrm{Sb}$) and/or precious metal ($\mathrm{Pt}\ensuremath{\rightarrow}\mathrm{Pd}$). We show isovolume series ${\mathrm{Ce}}_{3}{\mathrm{Bi}}_{4}{({\mathrm{Pt}}_{1\ensuremath{-}x}{\mathrm{Pd}}_{x})}_{3}$ fact substantially modified different radial extent $5d$ (Pt) and $4d$ (Pd) orbitals, while spin-orbit mediated changes minute. Combining experimental temperatures simulated hybridization functions, also predict effective masses ${m}^{*}$, finding excellent agreement many-body results ${\mathrm{Ce}}_{3}{\mathrm{Bi}}_{4}{\mathrm{Pt}}_{3}$. Our analysis motivates studying so-far unknown ${\mathrm{Ce}}_{3}{\mathrm{Sb}}_{4}{\mathrm{Pd}}_{3}$, ${m}^{*}/{m}_{\mathrm{band}}=O(10)$.