David A. Muller

Learn More
Micropatterning of single crystals for technological applications is a complex, multistep process. Nature provides alternative fabrication strategies, when crystals with exquisite micro-ornamentation directly develop within preorganized frameworks. We report a bio-inspired approach to growing large micropatterned single crystals. Micropatterned templates(More)
  • Adam W Tsen, Lola Brown, Mark P Levendorf, Fereshte Ghahari, Pinshane Y Huang, Robin W Havener +4 others
  • 2012
Graphene produced by chemical vapor deposition (CVD) is polycrystalline, and scattering of charge carriers at grain boundaries (GBs) could degrade its performance relative to exfoliated, single-crystal graphene. However, the electrical properties of GBs have so far been addressed indirectly without simultaneous knowledge of their locations and structures.(More)
High-performance metal-oxide-semiconductor field effect transistors ͑MOSFETs͒ on III–V semiconductors have long proven elusive. High-permittivity ͑high-␬͒ gate dielectrics may enable their fabrication. We have studied hafnium oxide and aluminum oxide grown on gallium arsenide by atomic layer deposition. As-deposited films are continuous and predominantly(More)
  • Takahiro Moriyama, Theodore J Gudmundsen, Pinshane Y Huang, Luqiao Liu, David A Muller, Daniel C Ralph +1 other
  • 2010
We have fabricated MgO-barrier magnetic tunnel junctions with a Co/Ni switching layer to reduce the demagnetizing field via interface anisotropy. With a fcc-͑111͒ oriented Co/Ni multilayer combined with an FeCoB insertion layer, the demagnetizing field is 2 kOe and the tunnel magnetoresistance can be as high as 106%. Room-temperature measurements of(More)
  • Pinshane Y Huang, Simon Kurasch, Anchal Srivastava, Viera Skakalova, Jani Kotakoski, Arkady V Krasheninnikov +6 others
  • 2012
Large-area graphene substrates provide a promising lab bench for synthesizing, manipulating, and characterizing low-dimensional materials, opening the door to high-resolution analyses of novel structures, such as two-dimensional (2D) glasses, that cannot be exfoliated and may not occur naturally. Here, we report the accidental discovery of a 2D silica glass(More)
  • Xu Cui, Gwan-Hyoung Lee, Young Duck Kim, Ghidewon Arefe, Pinshane Y Huang, Chul-Ho Lee +12 others
  • 2015
Atomically thin two-dimensional semiconductors such as MoS 2 hold great promise for electrical, optical and mechanical devices and display novel physical phenomena. However, the electron mobility of mono-and few-layer MoS 2 has so far been substantially below theoretically predicted limits, which has hampered efforts to observe its intrinsic quantum(More)
The miniaturization and integration of frequency-agile microwave circuits--relevant to electronically tunable filters, antennas, resonators and phase shifters--with microelectronics offers tantalizing device possibilities, yet requires thin films whose dielectric constant at gigahertz frequencies can be tuned by applying a quasi-static electric field.(More)
This article focuses on the development of a transparent and uniform understanding of possibilities for three-dimensional (3D) imaging in scanning transmission and confocal electron microscopes (STEMs and SCEMs), with an emphasis on the annular dark-field STEM (ADF-STEM), bright-field SCEM (BF-SCEM), and ADF-SCEM configurations. The incoherent imaging(More)
The high beam current and subangstrom resolution of aberration-corrected scanning transmission electron microscopes has enabled electron energy loss spectroscopy (EELS) mapping with atomic resolution. These spectral maps are often dose limited and spatially oversampled, leading to low counts/channel and are thus highly sensitive to errors in background(More)
Replacing platinum by a less precious metal such as palladium, is highly desirable for lowering the cost of fuel-cell electrocatalysts. However, the instability of palladium in the harsh environment of fuel-cell cathodes renders its commercial future bleak. Here we show that by incorporating trace amounts of gold in palladium-based ternary (Pd6CoCu)(More)