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Abstract Enhancing electron correlation in a weakly interacting topological system has great potential to promote correlated topological states of matter with extraordinary quantum properties. Here, the enhancement of electron correlation in a prototypical topological metal, namely iridium dioxide (IrO2), via doping with 3d transition metal vanadium is demonstrated. Single‐crystalline vanadium‐doped IrO2nanowires are synthesized through chemical vapor deposition where the nanowire yield and morphology are improved by creating rough surfaces on substrates. Vanadium doping leads to a dramatic decrease in Raman intensity without notable peak broadening, signifying the enhancement of electron correlation. The enhanced electron correlation is further evidenced by transport studies where the electrical resistivity is greatly increased and follows an unusual dependence on the temperature (T). The lattice thermal conductivity is suppressed by an order of magnitude via doping even at room temperature where phonon‐impurity scattering becomes less important. Density functional theory calculations suggest that the remarkable reduction of thermal conductivity arises from the complex phonon dispersion and reduced energy gap between phonon branches, which greatly enhances phase space for phonon–phonon Umklapp scattering. This work demonstrates a unique system combining 3d and 5d transition metals in isostructural materials to enrich the system with various types of interactions.
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This content will become publicly available on March 18, 2026
Integrals of products of Bessel functions: a perspective from the physics of Bloch electrons
Abstract Integrals of products of Bessel functions exhibit an intriguing feature: they may vanish identically, not due to an orthogonality property, but rather when certain conditions on the parameters specifying the integrand are satisfied. We provide a physical interpretation of this feature in the context of both single-particle and many-body properties of electrons on a lattice (“Bloch electrons“), namely, in terms of their density of states and umklapp scattering rate. (In an umklapp event, the change in the momentum of two colliding electrons is equal to a reciprocal lattice vector, which gives rise to a finite resistivity due to electron-electron interaction.) In this context, the vanishing of an integral follows simply from the condition that either the density of states vanishes due to the electron energy lying outside the band in which free propagation of electron waves is allowed, or that an umklapp process is kinematically forbidden due to the Fermi surface being smaller than a critical value.
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- Award ID(s):
- 2224000
- PAR ID:
- 10648019
- Publisher / Repository:
- IOPscience
- Date Published:
- Journal Name:
- Physica Scripta
- Volume:
- 100
- Issue:
- 4
- ISSN:
- 0031-8949
- Page Range / eLocation ID:
- 045229
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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