Design rules for modulation-doped AlAs quantum wells

Abstract

Thanks to their multi-valley, anisotropic, energy band structure, two-dimensional electron systems (2DESs) in modulation-doped AlAs quantum wells (QWs) provide a unique platform to investigate electron interaction physics and ballistic transport. Indeed, a plethora of phenomena unseen in other 2DESs have been observed over the past decade. However, a foundation for sample design is still lacking for AlAs 2DESs, limiting the means to achieve optimal quality samples. Here we present a systematic study on the fabrication of modulation-doped AlAs and GaAs QWs over a wide range of AlxGa1-xAs barrier alloy compositions. Our data indicate clear similarities in modulation doping mechanisms for AlAs and GaAs, and provide guidelines for the fabrication of very high quality AlAs 2DESs. We highlight the unprecedented quality of the fabricated AlAs samples by presenting the magnetotransport data for low density (~1X1011 cm2) AlAs 2DESs that exhibit high-order fractional quantum Hall signatures.

6 pages, 5 figures

References in corpus (11)

• Valley filter and valley valve in graphene
• Multicomponent fractional quantum Hall effect in graphene
• Valley susceptibility of an interacting two-dimensional electron system
• Observation of Quantum Hall Valley Skyrmions
• The Two-flux Composite Fermion Series of Fractional Quantum Hall States in Strained Si
• Valley polarization and susceptibility of composite fermions around nu=3/2
• Quantized conductance in an AlAs 2D electron system quantum point contact
• Transference of Transport Anisotropy to Composite Fermions
• Mobility versus quality in 2D semiconductor structures
• Spinless composite fermions in an ultra-high quality strained Ge quantum well
• Donor binding energy and thermally activated persistent photoconductivity in high mobility (001) AlAs quantum wells

Cited by in corpus (13)

• Understanding limits to mobility in ultra-high-mobility GaAs two-dimensional electron systems: The quest for 100 million cm${}^2$/Vs and beyond
• Unconventional anisotropic even-denominator fractional quantum Hall state in a system with mass anisotropy
• Multivalley two-dimensional electron system in an AlAs quantum well with mobility exceeding $2\times 10^6$ cm${}^2$V${}^{-1}$s${}^{-1}$
• Composite fermion pairing induced by Landau level mixing
• Record-quality GaAs two-dimensional hole systems
• Working principles of doping-well structures for high-mobility two-dimensional electron systems
• Direct observation of $\Gamma -X$ energy spectrum transition in narrow AlAs quantum wells
• Observation of fractional quantum Hall effect in an InAs quantum well
• Surface segregation and the Al problem in GaAs quantum wells
• Unveiling the charge distribution of a GaAs-based nanoelectronic device: A large experimental data-set approach
• Electron spectra in double quantum wells of different shapes
• Developing fractional quantum Hall states at $\nu$ = $\frac{1}{7}$ and $\frac{2}{11}$ in the presence of significant Landau level mixing
• Heterostructure design to achieve high quality, high density GaAs 2D electron system with $g$-factor tending to zero