{"title":"Shape and size effects on electronic thermodynamics in nanoscopic quantum dots","authors":"J.A. Gil-Corrales , C.A. Dagua-Conda , M.E. Mora-Ramos , A.L. Morales , C.A. Duque","doi":"10.1016/j.physe.2025.116228","DOIUrl":null,"url":null,"abstract":"<div><div>The thermodynamic properties of strongly confined semiconductor nanostructures are significantly influenced by their geometry because the thermal de Broglie wavelength of the particles is comparable to the size of the structure. GaAs quantum dots (QDs) are nanostructures that can be configured in various geometrical forms, which makes them excellent candidates for studying how geometrical variations affect their thermodynamic properties. In this work, we present the study of the thermodynamic properties of a GaAs QD in spherical, cylindrical, cubic, and pyramidal shapes, through the finite element method (FEM) considering external infinite confinement and the effective mass approximation. The design of QDs guarantees the same volume (V) and cross-sectional area (A) for each case, providing structures with similar size characteristics. We observe stepwise behaviors in the particle number and entropy as a function of chemical potential due to shape dependence for the highest confinement configuration, which agrees with the nature of the Fermi–Dirac distribution function. Finally, we present the effect of geometrical shape for all geometrical configurations of the QD. We compare the thermodynamic properties of each arrangement and investigate the heat capacity response for different temperatures.</div></div>","PeriodicalId":20181,"journal":{"name":"Physica E-low-dimensional Systems & Nanostructures","volume":"170 ","pages":"Article 116228"},"PeriodicalIF":2.9000,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Physica E-low-dimensional Systems & Nanostructures","FirstCategoryId":"101","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1386947725000530","RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"NANOSCIENCE & NANOTECHNOLOGY","Score":null,"Total":0}
Shape and size effects on electronic thermodynamics in nanoscopic quantum dots
The thermodynamic properties of strongly confined semiconductor nanostructures are significantly influenced by their geometry because the thermal de Broglie wavelength of the particles is comparable to the size of the structure. GaAs quantum dots (QDs) are nanostructures that can be configured in various geometrical forms, which makes them excellent candidates for studying how geometrical variations affect their thermodynamic properties. In this work, we present the study of the thermodynamic properties of a GaAs QD in spherical, cylindrical, cubic, and pyramidal shapes, through the finite element method (FEM) considering external infinite confinement and the effective mass approximation. The design of QDs guarantees the same volume (V) and cross-sectional area (A) for each case, providing structures with similar size characteristics. We observe stepwise behaviors in the particle number and entropy as a function of chemical potential due to shape dependence for the highest confinement configuration, which agrees with the nature of the Fermi–Dirac distribution function. Finally, we present the effect of geometrical shape for all geometrical configurations of the QD. We compare the thermodynamic properties of each arrangement and investigate the heat capacity response for different temperatures.
期刊介绍:
Physica E: Low-dimensional systems and nanostructures contains papers and invited review articles on the fundamental and applied aspects of physics in low-dimensional electron systems, in semiconductor heterostructures, oxide interfaces, quantum wells and superlattices, quantum wires and dots, novel quantum states of matter such as topological insulators, and Weyl semimetals.
Both theoretical and experimental contributions are invited. Topics suitable for publication in this journal include spin related phenomena, optical and transport properties, many-body effects, integer and fractional quantum Hall effects, quantum spin Hall effect, single electron effects and devices, Majorana fermions, and other novel phenomena.
Keywords:
• topological insulators/superconductors, majorana fermions, Wyel semimetals;
• quantum and neuromorphic computing/quantum information physics and devices based on low dimensional systems;
• layered superconductivity, low dimensional systems with superconducting proximity effect;
• 2D materials such as transition metal dichalcogenides;
• oxide heterostructures including ZnO, SrTiO3 etc;
• carbon nanostructures (graphene, carbon nanotubes, diamond NV center, etc.)
• quantum wells and superlattices;
• quantum Hall effect, quantum spin Hall effect, quantum anomalous Hall effect;
• optical- and phonons-related phenomena;
• magnetic-semiconductor structures;
• charge/spin-, magnon-, skyrmion-, Cooper pair- and majorana fermion- transport and tunneling;
• ultra-fast nonlinear optical phenomena;
• novel devices and applications (such as high performance sensor, solar cell, etc);
• novel growth and fabrication techniques for nanostructures