Inter-cluster separation induced change in charge transport mechanism in Ni40Pd60 nanoclusters
| Autor: | Chandrahas Bansal, D. Jaiswal Nagar, S. G. Praveen |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
0301 basic medicine
Materials science Alloy Physical system lcsh:Medicine Insulator (electricity) engineering.material Variable-range hopping Article Nanoclusters Metal 03 medical and health sciences 0302 clinical medicine Coulomb lcsh:Science Multidisciplinary Nanoscale materials lcsh:R Fermi surface 030104 developmental biology Chemical physics visual_art visual_art.visual_art_medium engineering lcsh:Q Condensed Matter::Strongly Correlated Electrons 030217 neurology & neurosurgery |
| Zdroj: | Scientific Reports Scientific Reports, Vol 9, Iss 1, Pp 1-11 (2019) |
| ISSN: | 2045-2322 |
| Popis: | Nanoclusters offer a fascinating possibility of studying the evolution of properties of a physical system by varying the number, size and inter-cluster separation of a given cluster to go from one limit to another. By systematically varying the inter-cluster separation in a nanocluster assembly of Ni40Pd60 alloy, that is known to be a metal in bulk, we observe an unusual and hitherto unreported, spatial dimension change as well as a change in the transport mechanism. In the nanocluster form, the temperature dependent resistance shows an activated behavior for virtually all inter-cluster separations, contrary to, the bulk metallic behaviour. At large average inter-cluster separation, the transport happens via three dimensional Efros-Shklovskii hopping, due to the opening of a Coulomb gap at the Fermi surface. With a reduction in the inter-cluster separation, the transport mechanism changes from three dimensional Efros-Shklovskii hopping to that of a three dimensional Mott variable range hopping (VRH) due to the closing up of the gap. With a further reduction in average inter-cluster separation, the three dimensional Mott VRH changes to that of a two dimensional Mott VRH with additional signatures of an insulator to a weak metal-like transition in this particular assembly. So, nanoclusters offer a paradigm for studying the important problem of evolution of charge transport in physical systems with the possibility of directly tuning the average inter-cluster separation enabling the system to go from insulating to metallic limit via intermediate changes in the charge transport mechanism. |
| Databáze: | OpenAIRE |
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