Quantum shape oscillations in the thermodynamic properties of confined electrons in core–shell nanostructures

• Quantum shape effect appears under the size-invariant shape transformations of stronglyconfined structures. Such a transformation distinctively influences the thermodynamicproperties of confined particles. Due to their characteristic geometry, core–shellnanostructures are good candidates for quantum shape effects to be observed. Here weinvestigate the thermodynamic properties of non-interacting degenerate electrons confined incore–shell nanowires consisting of an insulating core and a GaAs semiconducting shell. Wederive the expressions of shape-dependent thermodynamic quantities and show the existenceof a new type of quantum oscillations due to shape dependence, in chemical potential, internalenergy, entropy and specific heat of confined electrons.We provide physical understanding ofour results by invoking the quantum boundary layer concept and evaluating the distributions ofquantized energy levels on Fermi function and in state space. Besides the density, temperatureand size, the shape per se also becomes a control parameter on the Fermi energy of confinedelectrons, which provides a new mechanism for fine tuning the Fermi level and changing thepolarity of semiconductors.

Subject headings

NATURVETENSKAP  -- Fysik -- Den kondenserade materiens fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Condensed Matter Physics (hsv//eng)

Keyword

quantum shape effect

quantum confinement

quantum oscillations

thermodynamic properties

heat capacity

geometry effects

core–shell nanostructures

Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik

Physics with spec. in Atomic, Molecular and Condensed Matter Physics

Publication and Content Type

ref (subject category)

art (subject category)