title: Highly tensile-strained Ge/InAlAs nanocomposites.
abstract: Self-assembled nanocomposites have been extensively investigated due to the novel properties that can emerge when multiple material phases are combined. Growth of epitaxial nanocomposites using lattice-mismatched constituents also enables strain-engineering, which can be used to further enhance material properties. Here, we report self-assembled growth of highly tensile-strained Ge/In0.52Al0.48As (InAlAs) nanocomposites by using spontaneous phase separation. Transmission electron microscopy shows a high density of single-crystalline germanium nanostructures coherently embedded in InAlAs without extended defects, and Raman spectroscopy reveals a 3.8% biaxial tensile strain in the germanium nanostructures. We also show that the strain in the germanium nanostructures can be tuned to 5.3% by altering the lattice constant of the matrix material, illustrating the versatility of epitaxial nanocomposites for strain engineering. Photoluminescence and electroluminescence results are then discussed to illustrate the potential for realizing devices based on this nanocomposite material.
authors.affiliation: Department of Electrical Engineering, Yale University, New Haven, Connecticut 06511, USA.
authors.forename: Daehwan
authors.initials: D
authors.lastname: Jung
authors.affiliation: Department of Electrical Engineering, Yale University, New Haven, Connecticut 06511, USA.
authors.forename: Joseph
authors.initials: J
authors.lastname: Faucher
authors.affiliation: Department of Engineering Physics, École Polytechnique de Montreal, Montreal, Quebec, Canada H3C 3A7.
authors.forename: Samik
authors.initials: S
authors.lastname: Mukherjee
authors.affiliation: Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: Austin
authors.initials: A
authors.lastname: Akey
authors.affiliation: Department of Electrical and Computer Engineering, University of Texas at Austin, Austin, Texas 78758, USA.
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Ironside
authors.affiliation: Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27606, USA.
authors.forename: Matthew
authors.initials: M
authors.lastname: Cabral
authors.affiliation: Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27606, USA.
authors.forename: Xiahan
authors.initials: X
authors.lastname: Sang
authors.affiliation: Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27606, USA.
authors.forename: James
authors.initials: J
authors.lastname: Lebeau
authors.affiliation: Department of Electrical and Computer Engineering, University of Texas at Austin, Austin, Texas 78758, USA.
authors.forename: Seth R
authors.initials: SR
authors.lastname: Bank
authors.affiliation: Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: Tonio
authors.initials: T
authors.lastname: Buonassisi
authors.affiliation: Department of Engineering Physics, École Polytechnique de Montreal, Montreal, Quebec, Canada H3C 3A7.
authors.forename: Oussama
authors.initials: O
authors.lastname: Moutanabbir
authors.affiliation: Department of Electrical Engineering, Yale University, New Haven, Connecticut 06511, USA.|Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
authors.forename: Minjoo Larry
authors.initials: ML
authors.lastname: Lee