293 citations · 562 across the 14 of their papers we have counts for
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Diffusive Phonons in Nongray Nanostructures
Giuseppe Romano, Alexie M. Kolpak
Nanostructured semiconducting materials are promising candidates for thermoelectrics due to their potential to suppress phonon transport while preserving electrical properties. Mod…
Thermal Anisotropy Enhanced by Phonon Size Effects in Nanoporous Materials
Giuseppe Romano, Alexie M. Kolpak
While thermal anisotropicity is a desirable materials property for many applications, including transverse thermoelectrics and thermal management in electronic devices, it remains…
Directional Phonon Suppression Function as a Tool for the Identification of Ultralow Thermal Conductivity Materials
Giuseppe Romano, Alexie M. Kolpak
Boundary-engineering in nanostructures has the potential to dramatically impact the development of materials for high-efficiency conversion of thermal energy directly into electric…
Temperature-dependent thermal conductivity in nanoporous materials studied by the Boltzmann Transport Equation
Giuseppe Romano, Keivan Esfarjani, David A. Strubbe +2
Nanostructured materials exhibit low thermal conductivity because of the additional scattering due to phonon-boundary interactions. As these interactions are highly sensitive to th…
Electronic and magnetic properties of SrTiO3/LaAlO3 interfaces from first principles
Hanghui Chen, Alexie M. Kolpak, Sohrab Ismail-Beigi
A number of intriguing properties emerge upon the formation of the epitaxial interface between the insulating oxides LaAlO3 and SrTiO3. These properties, which include a quasi two-…
A First-Principles Study of the Electronic Reconstructions of LaAlO3/SrTiO3 Heterointerfaces and Their Variants
Hanghui Chen, Alexie M. Kolpak, Sohrab Ismail-Beigi
We present a first-principles study of the electronic structures and properties of ideal (atomically sharp) LaAlO3/SrTiO3 (001) heterointerfaces and their variants such as a new cl…
Fundamental asymmetry in interfacial electronic reconstruction between insulating oxides
Hanghui Chen, Alexie M. Kolpak, Sohrab Ismail-Beigi
We present an ab initio study of the (001) interfaces between two insulating perovskites, the polar LaAlO3 and the nonpolar SrTiO3. We observe an insulating-to-metallic transition…
Short-circuit boundary conditions in ferroelectric PbTiO thin films
Alexie M. Kolpak, Na Sai, Andrew M. Rappe
We examine the application of short-circuit electrical boundary conditions in density functional theory calculations of ferroelectric thin films. Modeling PbTiO films with Pt e…
Ferroelectricity in ultra-thin perovskite films
Na Sai, Alexie M. Kolpak, Andrew M. Rappe
We report studies of ferroelectricity in ultra-thin perovskite films with realistic electrodes. The results reveal stable ferroelectric states in thin films less than 10 Åthick wit…
Support-mediated activation and deactivation of Pt thin films
Valentino R. Cooper, Alexie M. Kolpak, Yashar Yourdshahyan +1
Using ab initio methods, we examine the the charge distribution at the interface of alpha-alumina-supported Pt films, and we consider the influence of this interface on CO adsorpti…