Effect of a skin-deep surface zone on formation of two-dimensional electron gas at a semiconductor surface

Abstract

Two dimensional electron gases (2DEGs) at surfaces and interfaces of semiconductors are described straightforwardly with a 1D self-consistent Poisson-Schrödinger scheme. However, their band energies have not been modeled correctly in this way. Using angle-resolved photoelectron spectroscopy we study the band structures of 2DEGs formed at sulfur-passivated surfaces of InAs(001) as a model system. Electronic properties of these surfaces are tuned by changing the S coverage, while keeping a high-quality interface, free of defects and with a constant doping density. In contrast to earlier studies we show that the Poisson-Schrödinger scheme predicts the 2DEG bands energies correctly but it is indispensable to take into account the existence of the physical surface. The surface substantially influences the band energies beyond simple electrostatics, by setting nontrivial boundary conditions for 2DEG wavefunctions.

arXiv comment9 pages, 7 figures, 2 tables

References in corpus (6)

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• Self-adjoint extensions of operators and the teaching of quantum mechanics
• Polaronic metal state at the LaAlO3/SrTiO3 interface
• Creation of high mobility two-dimensional electron gases via strain induced polarization at an otherwise nonpolar complex oxide interface
• Origin of the anomalous mass renormalization in metallic quantum well states of correlated oxide SrVO${}_3$
• QCAD Simulation and Optimization of Semiconductor Quantum Dots

Cited by in corpus (3)

• Quantum Confinement and Electronic Structure at the Surface of van der Waals Ferroelectric α-In${}_2$Se${}_3$
• Dirac energy spectrum and inverted band gap in metamorphic InAsSb/InSb superlattices
• On the origin of electron accumulation layer at clean InAs(111) surfaces