Weak localization competes with the quantum oscillations in a natural electronic superlattice: The case of Na1.5(PO2)4(WO3

Abstract

We report an investigation of the combined structural and electronic properties of the bronze Na 1.5 (PO 2 ) 4 (WO 3 ) 20 . Its low-dimensional structure and possible large reconstruction of the Fermi surface due to charge density wave instability make this bulk material a natural superlattice with a reduced number of carriers and Fermi energy. Signatures of multilayered two-dimensional (2D) electron weak localization are consequently reported, with an enhanced influence of quantum oscillations. A crossover between these two antagonistic entities, previously observed only in genuine low-dimensional materials and devices, is shown to occur in a bulk crystal due to its hidden 2D nature.

Nature of electrons from oxygen vacancies and polar catastrophe at LaAlO3/SrTiO3 interfaces

“…It is worthy noticing that the negative MR in our samples persists up to 9 T from 50 K to 30 K, which indicated that the weak localization effect persists up to the magnetic field of 9 T. This result agrees with some typical low-dimensional conduction systems [17,40,41]. However, in some other lowdimensional conduction systems [42,43], the MR is negative for moderate magnetic field, followed by a positive MR at higher magnetic field, which indicated that some other effect like regular orbital scattering may become more important at higher magnetic field. The dominating factors for the difference in low-dimensional conduction systems need to be further investigated.…”