Walter P. Murphy Professor of Materials Science and Engineering and Electrical Engineering and Computer Science

BS, metallurgy and material science, 1968 University of Pennsylvania

PhD, materials science, 1973 Massachussets Institute of Technology

 

Contact Info

Electronic and photonic materials

     Our laboratory develops thin films and nanostructures for electronic, magnetic, and photonic materials applications, with emphasis on semiconductor and ferroic oxide thin films. Metal-organic vapor phase epitaxy techniques have been developed and applied to both narrow band gap and wide band gap compound semiconductors including InMnSb, InMnAs and InGaN alloy semiconductors. Their electronic, optical and magnetic properties are characterized using a variety of techniques including photoluminescence spectroscopy, magneto-optic Kerr effect and magnetoresistance measurements. Ferromagnetic InMnAs is being developed as a spintronic material for nanoelectronics.  Heterojunction spintronic devices are fabricated and their transport properties measured.
     We are synthesizing epitaxial oxides by metal-organic vapor phase epitaxy and molecular beam epitaxy for applications in nanophotonics and nanomagnetics.  Emphasis is currently on the development of ferroelectric and ferromagnetics oxide epitaxial thin films and superlattices. We measure their nonlinear optical properties as well as their magnetic and magneto-electric properties. The ferroelectric domain structure is determined from electro-optical and microwave property measurements. Development of thin film photonic crystals for electro-optic modulator, laser, and optical amplifiers for opto-electronic integrated circuits (OEICs) is under way.

Research Interests

Associations and Awards

Walter P. Murphy Professor of Materials Science and Engineering

Fellow of the American Physical Society, 2003

Editorial board, Journal of Electronic Materials, 1982–88; Associate Editor, 1997–present

Chair, electronic, magnetic, and photo division of TMS–AIME, 1993–95

Board of directors, TMS, 1993–98

Fellow, ASM, 1996

President, TMS, 1996

Board of trustees, AIME, 1996–98

President, TMS Foundation, 1997

Selected Recent Publications

“Dendritic nanowire growth mediated by self-assembled catalyst,” S. J. May, J-G Zheng, B. W. Wessels and L. J. Lauhon, Adv. Materials, 17 598-602 (2005).

 

"Local Environment of Ferromagnetically Ordered Mn in Epitaxial InMnAs," with P. T. Chiu, B. W. Wessels, D. J. Keavney, and J. W. Freeland, Appl. Phys. Lett., 86 072505, 1-3 (2005).

 

  “Nonlinear photonic crystal waveguide structures based on barium titanate thin films and their optical properties,” with Z.F. Liu, P.T. Lin, B. W. Wessels et al., Appl. Phys. Lett., 90 201104, 2007.

 

“Epitaxial Fe₃O₄ on SrTiO₃ characterized by transmission electron microscopy,” with J.G. Zheng, G.E. Sterbinsky, J. Cheng, and B. W. Wessels, J. Vac. Sci. Technol., B 25(4), 2007.

 

“Ferroelectric epitaxial thin films for integrated optics,” B. W. Wessels, Ann. Rev. Mater. Res.,  37 659 (2007).

“Dependence of magnetic circular dichroism on doping and temperature dependence in In1-xMnxAs epitaxial films,” P. T. Chiu and B. W. Wessels, Phys. Rev., B 76 165201 (2007).