Skip to Main Content U.S. Department of Energy
Fundamental and Computational Sciences Directorate

Staff information

Tim Droubay

Materials Sciences
Scientist
Pacific Northwest National Laboratory
PO Box 999
MSIN: K8-87
Richland, WA 99352
509/371-6488

PNNL Publications

2012

  • Kaspar TC, and T Droubay. 2012. "Variation in band offsets at ZnO/Sn:In2O3 (ITO) heterojunctions measured by x-ray photoelectron spectroscopy." Journal of Vacuum Science and Technology A--Vacuum, Surfaces and Films 30(4): 04D112.  doi:10.1116/1.4719541
  • Chambers SA, T Droubay, C Capan, and G Sun. 2012. "Unintentional F doping of SrTiO3(001) etched in HF acid-structure and electronic properties." Surface Science 606(3-4):554-558.  doi:10.1016/j.susc.2011.11.029
  • Look DC, T Droubay, and SA Chambers. 2012. "Stable highly conductive ZnO via reduction of Zn vacancies." Applied Physics Letters 101(10):Article No. 102101.  doi:10.1063/1.4748869
  • Varga T, T Droubay, ME Bowden, P Nachimuthu, V Shutthanandan, TB Bolin, WA Shelton, and SA Chambers. 2012. "Epitaxial growth of NiTiO3 with a distorted ilmenite structure." Thin Solid Films 520(17):5534-5541.  doi:10.1016/j.tsf.2012.04.060

2011

  • Kaspar TC, T Droubay, and JE Jaffe. 2011. "ZnO/Sn:In2O3 and ZnO/CdTe band offsets for extremely thin absorber photovoltaics ." Applied Physics Letters 99(26):263504.  doi:10.1063/1.3672218
  • Qiao L, T Droubay, ME Bowden, V Shutthanandan, TC Kaspar, and SA Chambers. 2011. "LaCrO3 heteroepitaxy on SrTiO3(001) by molecular beam epitaxy ." Applied Physics Letters 99(6):Art. No. 061904.  doi:10.1063/1.3624473
  • Qiao L, T Droubay, T Varga, ME Bowden, V Shutthanandan, Z Zhu, TC Kaspar, and SA Chambers. 2011. "Epitaxial growth, structure and intermixing at the LaAlO3/SrTiO3 interface as the film stoichiometry is varied." Physical Review. B, Condensed Matter and Materials Physics 83(8):085408.  doi:10.1103/PhysRevB.83.085408
  • Qiao L, T Droubay, TC Kaspar, PV Sushko, and SA Chambers. 2011. "Cation mixing, band offsets and electric fields at LaAlO3/SrTiO3(001) heterojunctions with variable La:Al atom ratio." Surface Science 605(15-16):1381-1387.  doi:10.1016/j.susc.2011.04.035
  • Chambers SA, L Qiao, T Droubay, TC Kaspar, BW Arey, and PV Sushko. 2011. "Band Alignment, Built-In Potential, and the Absence of Conductivity at the LaCrO3/SrTiO3(001) Heterojunction." Physical Review Letters 107(20):Article No. 206802.  doi:10.1103/PhysRevLett.107.206802
  • Droubay T, CI Pearce, ES Ilton, MH Engelhard, W Jiang, SM Heald, E Arenholz, V Shutthanandan, and KM Rosso. 2011. "Epitaxial Fe3-xTixO4 films from magnetite to ulvöspinel by pulsed laser deposition." Physical Review. B, Condensed Matter 84(12):Article No. 125443.  doi:10.1103/PhysRevB.84.125443
  • Look D, T Droubay, JS McCloy, Z Zhu, and SA Chambers. 2011. "Ga-doped ZnO grown by pulsed laser deposition in H2: the roles of Ga and H." Journal of Vacuum Science and Technology A--Vacuum, Surfaces and Films 29(3):Article No.: 03A102.  doi:10.1116/1.3523296
  • McCloy JS, RK Kukkadapu, JV Crum, BR Johnson, and T Droubay. 2011. "Size Effects on Gamma Radiation Response of Magnetic Properties of Barium Hexaferrite Powders." Journal of Applied Physics 110(11):Article No. 113912.  doi:10.1063/1.3665769
  • Zhao B, TC Kaspar, T Droubay, JS McCloy, ME Bowden, V Shutthanandan, SM Heald, and SA Chambers. 2011. "Electrical transport properties of Ti-doped Fe2O3(0001) epitaxial films." Physical Review. B, Condensed Matter 84(24):245325.  doi:10.1103/PhysRevB.84.245325

2010

  • Kaspar TC, T Droubay, and SA Chambers. 2010. "Atomic oxygen flux determined by mixed-phase Ag/Ag2O deposition." Thin Solid Films 519(2):635-640.  doi:10.1016/j.tsf.2010.08.081
  • Kaspar TC, T Droubay, SA Chambers, and PS Bagus. 2010. "Spectroscopic evidence for Ag(III) in highly oxidized silver films by x-ray photoelectron spectroscopy." Journal of Physical Chemistry C 114(49):21562-21571.  doi:10.1021/jp107914e
  • Qiao L, T Droubay, V Shutthanandan, Z Zhu, PV Sushko, and SA Chambers. 2010. "Thermodynamic Instability at the Stoichiometric LaAlO3/SrTiO3(001) Interface." Journal of Physics. Condensed matter 22(31):Art. No. 312201.  doi:10.1088/0953-8984/22/31/312201
  • Baer DR, MH Engelhard, AS Lea, P Nachimuthu, T Droubay, J Kim, B Lee, C Mathews, RL Opila, LV Saraf, WF Stickle, R Wallace, and BS Wright. 2010. "Comparison of the Sputter Rates of Oxide Films Relative to the Sputter Rate of SiO2." Journal of Vacuum Science and Technology A--Vacuum, Surfaces and Films 28(5):1060-1072.  doi:10.1116/1.3456123
  • Chambers SA, MH Engelhard, V Shutthanandan, Z Zhu, T Droubay, L Qiao, PV Sushko, T Feng, HD Lee, T Gustafsson, E Garfunkel, AB Shah, JM Zuo, and QM Ramasse. 2010. "Instability, intermixing and electronic structure at the epitaxial LaAlO3/SrTiO3(001) heterojunction." Surface Science Reports 65(10-12):317-352.  doi:10.1016/j.surfrep.2010.09.001
  • Droubay T, L Qiao, TC Kaspar, MH Engelhard, V Shutthanandan, and SA Chambers. 2010. "Non-stoichiometric material transfer in the pulsed laser deposition of LaAlO3." Applied Physics Letters 97(12):124105.  doi:10.1063/1.3487778
  • Jaffe JE, TC Kaspar, T Droubay, T Varga, ME Bowden, and GJ Exarhos. 2010. "Electronic and defect structure of CuSCN." Journal of Physical Chemistry C 114(19):9111-9117.  doi:10.1021/jp101586q
  • Johnson CA, KR Kittilstved, TC Kaspar, T Droubay, SA Chambers, GM Salley, and DR Gamelin. 2010. "Mid-Gap Electronic States in Zn1 xMnxO." Physical Review. B, Condensed Matter 82(11):Art. No. 115202. 
  • Johs A, L Shi, T Droubay, JF Ankner, and L Liang. 2010. "Characterization of the Decaheme c-Type Cytochrome OmcA in Solution and on Hematite Surfaces by Small Angle X-Ray Scattering and Neutron Reflectometry." Biophysical Journal 98(12):3035-3043. 
  • McCloy JS, JV Ryan, T Droubay, TC Kaspar, SA Chambers, and D Look. 2010. "Magnetotransport Properties of High Quality Co:ZnO and Mn:ZnO Single Crystal Pulsed Laser Deposition films: Pitfalls Associated with Magnetotransport on High Resistivity Materials ." Review of Scientific Instruments 81(6):Art. No. 063902.  doi:10.1063/1.3436648
  • Warner CL, S Addleman, AD Cinson, T Droubay, MH Engelhard, MA Nash, W Yantasee, and MG Warner. 2010. "High-Performance, Superparamagnetic, Nanoparticle-Based Heavy Metal Sorbents for Removal of Contaminants from Natural Waters." ChemSusChem 3(6):749-757.  doi:10.1002/cssc.201000027

2009

  • Warner MG, CL Warner, RS Addleman, T Droubay, MH Engelhard, JD Davidson, AD Cinson, MA Nash, and W Yantasee. 2009. "Synthesis of Functionalized Superparamagnetic Iron Oxide Nanoparticles from a Common Precursor and their Application as Heavy Metal and Actinide Sorbents." In Abstracts of Papers of the 237th ACS National Meeting, March 22-26, 2009, Salt Lake City, Utah, pp. COLL-465.  American Chemical Society, Washington DC. 
  • Droubay T, TC Kaspar, BP Kaspar, and SA Chambers. 2009. "Cation dopant distributions in nanostructures of transition-metal doped ZnO:Monte Carlo simulations." Physical Review. B, Condensed Matter and Materials Physics 79(7):Art. No. 075324. 
  • Droubay T, D Keavney, TC Kaspar, SM Heald, CM Wang, CA Johnson, KM Whitaker, DR Gamelin, and SA Chambers. 2009. "Correlated substitution in paramagnetic Mn2+-doped ZnO epitaxial films." Physical Review. B, Condensed Matter and Materials Physics 79(15):Article number:155203. 
  • Heald SM, TC Kaspar, T Droubay, and SA Chambers. 2009. "Characterization of Thin Films by XAFS: Application to Spintronics Materials." In Materials Science and Technology 2009 Conference and Exhibition, pp. 688-697.  ASM International, Warrendale, PA. 
  • Heald SM, TC Kaspar, T Droubay, V Shutthanandan, SA Chambers, A Mokhtari, AJ Behan, HJ Blythe, JR Neal, M Fox, and G Gehring. 2009. "X-ray absorption fine structure and magnetization characterization of the metallic Co component in Co-doped ZnO thin films ." Physical Review. B, Condensed Matter 79(7):Art. No. 075202. 
  • Lower BH, R Yongsunthon, L Shi, L Wildling, HJ Gruber, NS Wigginton, CL Reardon, GE Pinchuk, T Droubay, JF Boily, and S Lower. 2009. "Antibody recognition force microscopy shows that outer membrane cytochromes OmcA and MtrC are expressed on the exterior surface of Shewanella oneidensis MR-1." Applied and Environmental Microbiology 75(9):2931-2935. 

2008

  • Kaspar TC, T Droubay, SM Heald, MH Engelhard, P Nachimuthu, and SA Chambers. 2008. "Hidden Ferromagnetic Secondary Phases in Cobalt-doped ZnO Epitaxial Thin Films." Physical Review. B, Condensed Matter 77(20):201303.  doi:10.1103/PhysRevB.77.201303
  • Kaspar TC, T Droubay, SM Heald, P Nachimuthu, CM Wang, V Shutthanandan, CA Johnson, DR Gamelin, and SA Chambers. 2008. "Lack of ferromagnetism in n-type cobalt-doped ZnO epitaxial thin films." New Journal of Physics 10:Art. No. 055010.  doi:10.1088/1367-2630/10/5/055010
  • Eggleston CM, J Voros, L Shi, BH Lower, T Droubay, and PJ Colberg. 2008. "Binding and Direct Electrochemistry of OmcA, an Outer-Membrane Cytochrome from an Iron Reducing Bacterium, with Oxide Electrodes: A Candidate Biofuel Cell System." Inorganica Chimica Acta 361(3):769-777.  doi:10.1016/j.ica.2007.07.015
  • Li Y, TC Kaspar, T Droubay, AG Joly, P Nachimuthu, Z Zhu, V Shutthanandan, and SA Chambers. 2008. "A Study of H and D doped ZnO epitaxial films grown by pulsed laser deposition." Journal of Applied Physics 104(5):Article no. 053711.  doi:10.1063/1.2975219
  • Li Y, TC Kaspar, T Droubay, Z Zhu, V Shutthanandan, P Nachimuthu, and SA Chambers. 2008. "Electronic properties of H and D doped ZnO epitaxial films." Applied Physics Letters 92(15):Art. No. 152105. 

2007

  • Lower BH, L Shi, R Yongsunthon, T Droubay, DE Mccready, and S Lower. 2007. "Specific Bonds between an Iron Oxide Surface and Outer Membrane Cytochromes MtrC and OmcA from Shewanella oneidensis MR-1." Journal of Bacteriology 189(13):4944-4952.  doi:10.1128/JB.01518-06
  • Shao R, CM Wang, DE McCready, T Droubay, and SA Chambers. 2007. "Growth and structure of MBE grown TiO2 anatase films with rutile nano-crystallites ." Surface Science 601(6):1582-1589.  doi:10.1016/j.susc.2007.01.039
  • Cai M, SC Langford, JT Dickinson, G Xiong, T Droubay, AG Joly, KM Beck, and WP Hess. 2007. "An In Situ Study of the Martensitic Transformation in Shape Memory Alloys Using Photoemission Electron Microscopy." Journal of Nuclear Materials 361(2-3):306-312.  doi:10.1016/j.jnucmat.2006.12.008
  • Cai M, SC Langford, MJ Wu, WM Huang, G Xiong, T Droubay, AG Joly, K Beck, WP Hess, and JT Dickinson. 2007. "Study of Martensitic Phase transformation in a NiTiCu Thin Film Shape Memory Alloy Using Photoelectron Emission Microscopy." Advanced Functional Materials 17(1):161-167.  doi:10.1002/adfm.200600611
  • Droubay T, KM Rosso, SM Heald, DE Mccready, CM Wang, and SA Chambers. 2007. "Structure, Magnetism and Conductivity in Epitaxial Ti-doped ?-Fe2O3 Hematite: Experiment and density functional theory calculations." Physical Review. B, Condensed Matter and Materials Physics 75(10):, doi:10.1103/PhysRevB.75.104412
  • Xiong G, R Shao, T Droubay, AG Joly, KM Beck, SA Chambers, and WP Hess. 2007. "Photoemission Electron Microscopy of TiO2 Anatase Films Embedded with Rutile Nanocrystals." Advanced Functional Materials 17(13):2133-2138.  doi:10.1002/adfm.200700146

2006

  • Kaspar TC, T Droubay, DE McCready, P Nachimuthu, SM Heald, CM Wang, AS Lea, V Shutthanandan, SA Chambers, and MF Toney. 2006. "Magnetic properties of epitaxial Co-doped anatase TiO2 thin films with excellent structural quality." Journal of Vacuum Science and Technology B--Microelectronics and Nanometer Structures 24(4):2012-2017.  doi:10.1116/1.2216723
  • Kaspar TC, T Droubay, V Shutthanandan, SM Heald, CM Wang, DE McCready, S Thevuthasan, JD Bryan, DR Gamelin, AJ Kellock, MF Toney, X Hong, C Ahn, and SA Chambers. 2006. "Ferromagnetism and structure of epitaxial Cr-doped anatase TiO2 thin films." Physical Review. B, Condensed Matter and Materials Physics 73(15):155327 (12 p.).  doi:10.1103/PhysRevB.73.155327
  • Chambers SA, T Droubay, CM Wang, KM Rosso, SM Heald, SA Schwartz, KR Kittilstved, and DR Gamelin. 2006. "Ferromagnetism in Oxide Semiconductors ." Materials Today 9(11):28-35. 
  • Shutthanandan V, S Thevuthasan, T Droubay, SM Heald, MH Engelhard, DE McCready, SA Chambers, P Nachimuthu, and BS Mun. 2006. "Synthesis of Room-Temperature Ferromagnetic Cr-doped TiO2(110) Rutile Single Crystals using Ion Implantation." Nuclear Instruments and Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms 242(1-2):198-200.  doi:10.1016/j.nimb.2005.08.149
  • Shutthanandan V, S Thevuthasan, T Droubay, TC Kaspar, A Punnoose, J Hays, and SA Chambers. 2006. "Quantification of Dopant Concentrations in Diluted Magnetic Semiconductors using Ion Beam Techniques." Nuclear Instruments and Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms 249(1-2):402-405.  doi:10.1016/j.nimb.2006.04.038

2005

  • Droubay T, SM Heald, V Shutthanandan, S Thevuthasan, SA Chambers, and J Osterwalder. 2005. "Cr-doped TiO2 Anatase- A Ferromagnetic Insulator ." Journal of Applied Physics 97:046103. 
  • Kaspar TC, T Droubay, CM Wang, SM Heald, AS Lea, and SA Chambers. 2005. "Co-doped Anatase TiO2 Heteroepitaxy on Si(001)." Journal of Applied Physics 97(7):073511-073511-10.  doi:10.1063/1.1868854
  • Kaspar TC, SM Heald, CM Wang, JD Bryan, T Droubay, V Shutthanandan, S Thevuthasan, DE McCready, AJ Kellock, DR Gamelin, and SA Chambers. 2005. "Negligible Magnetism in Excellent Structural Quality CrxTi1-xO2 Anatase: Contrast with High-Tc Ferromagnetism in Structurally Defective CrxTi1-xO2." Physical Review Letters 95:217203.  doi:10.1103/PhysRevLett.95.217203
  • Cai M, SC Langford, T Dickinson, WM Huang, Q He, T Droubay, and DR Baer. 2005. "Study of Martensitic Transformation in a CuZnAl Shape Memory Alloy using Photoemission." In Proceedings of the International Conference on Mechanical Engineering and Mechanics (ICMEM2005) , ed. RC Batra and L Qian, pp. 1123-1127.  Science Press, Monmouth Junction, NJ. 
  • Chambers SA, T Droubay, and TC Kaspar. 2005. "Epitaxial Growth and Properties of Magnetically Doped TiO2." Chapter 7 in Thin Films and Heterostructures for Oxide Electronics, ed. Satishchandra B. Ogale, pp. 219-247.  Springer, New York, NY. 
  • Heald SM, SA Chambers, and T Droubay. 2005. "XAFS study of CoxTi1-xO2-x-anatase." Physica Scripta T115:597-599.  doi:10.1238/Physica.Topical.115a00597
  • Heald SM, SA Chambers, and T Droubay. 2005. "XAFS Study of Epitaxial CoxTi1-xO2-x Anatase." In 12th International Conference on X-ray Absorption FIne Structure held in Malmo, Sweden, June, 2003, ed. N. Martensson, pp. 597-599.  Royal Swedish Academy of Sciences, Stockholm, Sweden. 
  • Osterwalder J, T Droubay, TC Kaspar, JR Williams, CM Wang, and SA Chambers. 2005. "Growth of Cr-doped TiO2 Films in the Rutile and Anatase Structures by Oxygen Plasma Assisted Molecular Beam Epitaxy ." Thin Solid Films 484(1-2):289-298. 
  • Sasahara A, T Droubay, SA Chambers, H Uetsuka, and H Onishi. 2005. "Topography of Anatase TiO2 Film Synthesized on LaAlO3(001) ." Nanotechnology 16(3):S18-S21. 
  • Wang CM, V Shutthanandan, S Thevuthasan, T Droubay, and SA Chambers. 2005. "Microstructure of Co-doped TiO2 (110) Rutile by Ion Implantation." Journal of Applied Physics 97(7):99-104. 

2004

  • Chambers SA, T Droubay, TC Kaspar, and MS Gutowski. 2004. "Accurate Valence Band Maximum Determination for SrTiO3(001) ." Surface Science 554(2-3):81-89. 
  • Chambers SA, T Droubay, TC Kaspar, and MS Gutowski. 2004. "Experimental Determination of Valence Band Maxima for SrTiO3, TiO2, and SrO and the Associated Valence Band Offsets with Si(001)." Journal of Vacuum Science and Technology B--Microelectronics and Nanometer Structures 22(4):2205-2215. 
  • Kim YJ, S Thevuthasan, T Droubay, AS Lea, CM Wang, V Shutthanandan, SA Chambers, R Sears, B Taylor, and B Sinkovic. 2004. "Growth and Properties of molecular beam epitaxially grown ferromagnetic Fe-doped TiO2 rutile films on TiO2." Applied Physics Letters 84(18):3531-3533. 
  • Shutthanandan V, S Thevuthasan, SM Heald, T Droubay, MH Engelhard, TC Kaspar, DE McCready, LV Saraf, SA Chambers, BS Mun, NM Hamdan, P Nachimuthu, B Taylor, R Sears, and B Sinkovic. 2004. "Room Temperature Ferromagnetism in Ion-implanted Co-doped TiO2(110) Rutile." Applied Physics Letters 84(22):4466-4468. 
  • Shutthanandan V, S Thevuthasan, SM Heald, T Droubay, MH Engelhard, TC Kaspar, DE McCready, LV Saraf, SA Chambers, BS Mun, NM Hamdan, P Nachimuthu, B Taylor, R Sears, and B Sinkovic. 2004. "Room-Temperature Ferromagnetism in Ion-Implanted Co-Doped TiO2(110) Rutile." Applied Physics Letters 84(22):4466-4468. 

2003

  • Chambers SA, T Droubay, CM Wang, AS Lea, RFC Farrow, L Folks, V Deline, and S Anders. 2003. "Clusters and Magnetism in Epitaxial Co-doped TiO2 Anatase." Applied Physics Letters 82(8):1257-1259. 
  • Chambers SA, SM Heald, and T Droubay. 2003. "Local Co Structure in Epitaxial Cox Ti1-xO2-x Anatase." Physical Review. B, Condensed Matter and Materials Physics 67(10):22-25, art. no. 100401. 
  • Tuan AC, TC Kaspar, T Droubay, JW Rogers, Jr, and SA Chambers. 2003. "Band Offsets for the Epitaxial TiO2/SrTiO3/Si(001) System." Applied Physics Letters 83(18):3734-3736. 

2002

  • Altman EI, T Droubay, and SA Chambers. 2002. "Growth of MoO3 films by oxygen plasma assisted molecular beam epitaxy." Thin Solid Films 414(2):205-215. 
  • Chambers SA, T Droubay, DR Jennison, and TK Mattsson. 2002. "Laminar Growth of Ultrathin Metal Films on Metal Oxides: Co on Hydroxylated alpha-Al2O3(0001)." Science 297(5582):827-831. 
  • Chambers SA, CM Wang, S Thevuthasan, T Droubay, DE McCready, AS Lea, V Shutthanandan, and CF Windisch, Jr. 2002. "Epitaxial Growth and Properties of MBE Grown Ferromagnetic Co-doped TiO2 Anatase Films on SrTiO3(001) and LaAlO3(001)." Thin Solid Films 418(2):197-210. 

2001

  • Droubay T, and SA Chambers. 2001. "Surface Sensitive Fe 2p Photoemission Spectra for alpha-Fe2O3 (0001) - The Influence of Symmetry and Crystal-Field Strength." Physical Review. B, Condensed Matter 64(20):205414-205420. 
  • Chambers SA, and T Droubay. 2001. "The Role of Oxide Ionicity in Electronic Screening at Oxide/Metal Interfaces." Physical Review. B, Condensed Matter 64:075410-1 - 075410-6. 

Fundamental & Computational Sciences

Research Areas

Divisions

Research Highlights

View All Research Highlights & Staff Accomplishments

RSS Feed

Contacts