Dr. Stephen Ducharme Dr. Ducharme's Web Page email: Dr. Ducharme Vice Chair - Physics and Astronomy Dr. Ducharme's Web Page Dr. Ducharme's Publications NCMN Homepage

Dr. Stephen Ducharme, Professor
Physics & Astronomy
University of Nebraska - Lincoln
310F T. Jorgensen Hall
Lincoln, Nebraska 68588-0299
office: (402) 472-8590
lab: (402) 472-8644
email:sducharme1@unl.edu
Ducharme's website

Current Research

Ferroelectric Polymers: Crystalline Langmuir-Blodgett films of poly vinylidene fluoride and its copolymers as thin as one nanometer are the first truly two-dimensional ferroelectrics and have several potential applications. This work involves a multi-disciplinary collaboration with groups led by V. M. Fridkin at the Institute of Crystallography, Russian Academy of Sciences, Moscow; J. Li at the University of Washington; H. Kohlstedt at the Institut fûr Festkörperforschung in Jülich, Germany; S. Kalinin at Oak Ridge National Laboratory; S. Nakhmanson at Argonne National Laboratory; and the J. A. Woollam Co. Collaborations within the NCMN involve groups led by J. M. Takacs (Chemistry), S. Adenwalla and A. Gruverman (Physics), R. Saraf (Chemical Engineering), and Y. Lu (Electrical Engineering).

Fundamental studies focus on the properties of the ferroelectric polymer LB films, such as, the phase diagram, switching dynamics, dielectric properties, properties of nanostructured films, and development of new ferroelectric polymers. Applied studies focus on the application of the ferroelectric polymer LB films to nonvolatile random-access memories, pyroelectric infrared imaging devices, and high-energy-density capacitors. Notable accomplishments include the discovery of two-dimensional ferroelectricity, the first measurements of the intrinsic ferroelectric coercive field and intrinsic switching kinetics, development of a ferroelectric integrated polymer-silicon nonvolatile access memory element, discovery of ferroelectric nanomesas as small as 10 nm high by 100 nm in diameter.

Recent Publications

108. “Tuning the Energy Level Offset of Donor and Acceptor with Ferroelectric Dipole Layers for Increased Efficiency in Bilayer Organic Photovoltaic Cells,” Bin Yang, Yongbo Yuan, Shashi Poddar, Pankaj Sharma, Rafal Korlacki, Stephen Ducharme, Alexei Gruverman, Ravi Saraf and Jinsong Huang, Advanced Materials 24, 1455-60 (2012).

107. “The sweep rate dependence of the electrical control of magnetic coercivity,” A. Mardana, S. Ducharme, S. Adenwalla, J. Applied Physics 111, 07C708 (2012).

106. “Homogeneous switching in ultrathin ferroelectric films,” R. V. Gaynutdinov, S. G. Yudin, S. Ducharme, V. M. Fridkin, J. Physics: Condensed Matter 24, 15902 (2012).

105. “Electrical Control of Photoluminescence Wavelength from Semiconductor Quantum Dots in a Ferroelectric Polymer Matrix,” R. Korlacki, R. F. Saraf, S. Ducharme, Applied Physics Letters 99, 153112 (2011).

104. “Polarization switching at the nanoscale in ferroelectric copolymer thin films,” R. V. Gaynutdinov, S. Mitko, S. G. Yudin, V. M. Fridkin, S. Ducharme, Applied Physics Letters 99, 142804 (2011).

103. “Orientational Imaging in Polar Polymers by Piezoresponse Force Microscopy,” Pankaj Sharma, Dong Wu, Shashi Poddar, Timothy J. Reece, Stephen Ducharme and Alexei Gruverman, J. Applied Physics 110, 052010 (2011).

102. “Cluster Synthesis and Improved Dielectric Properties of Monodisperse TiO2-Vinylidine Fluoride Oligomer Nanocomposites,” B. Balasubramanian, K. L. Kraemer, Shah R. Valloppilly, S. Ducharme, D. J. Sellmyer, and Stephen Ducharme, Nanotechnology 22, 405605 (2011).

101. “Ferroelectric Control of Magnetic Anisotropy,” A. Mardana, S. Ducharme, S. Adenwalla, Nano Letters 11, 3862-67 (2011).

100. “High-Resolution Studies of Domain Switching Behavior in Nanostructured Ferroelectric Polymers,” Pankaj Sharma, Timothy J. Reece, Stephen Ducharme and Alexei Gruverman, Nano Letters 11, 1970-75 (2011).

99. “Polarization patterning by laser-induced phase change in ferroelectric polymer films,” C. M. Othon, S. Ducharme, Applied Physics A 104, 727-31 (2011).

98. “Efficiency enhancement in organic solar cells with ferroelectric polymers,” Yongbo Yuan, Timothy J. Reece, Stephen Ducharme, Pankaj Sharma, Alexei Gruverman, Yang Yang, Jinsong Huang, Nature Materials 11 (3), 296-302 (2011).

97. “Magnetoelectric Effects In Ferromagnetic Cobalt / Ferroelectric Copolymer Multilayer Films,” A. Mardana, Mengjun Bai, A. Baruth, Stephen Ducharme, S. Adenwalla, Applied Physics Letters 97, 112904 (2010).

96. “Investigation of State Retention in Metal-Ferroelectric-Insulator-Semiconductor Structures Based on Langmuir-Blodgett (LB) Copolymer Films,” T. J. Reece, A. Gerber, H. Kohlstedt, S. Ducharme, J. Applied Physics 108, 024109 (2010).

95. “Why Ferroelectric Polyvinylidene Fluoride is Special,” M. Poulsen, S. Ducharme, IEEE Transactions on Dielectrics and Electrical Insulation 17 (4), 1028-35 (2010).

94. “Ferroelectric field effect transistor using very thin ferroelectric polyvinylidene fluoride copolymer Langmuir-Blodgett films as gate dielectrics,” A. Gerber, M. Fitsilis, R. Waser, T. J. Reece, E. Rije, S. Ducharme, H. Kohlstedt, J. Applied Physics 107, 124119 (2010).

93. “Vibrational properties of ferroelectric b-vinylidene fluoride polymers and oligomers,” S. M. Nakhmanson, R. Korlacki, S. Ducharme, J. M. Takacs, Physical Review B 81, 174120.1-8 (2010); Virtual Journal of Biological Physics Research 19 (11), 1 June 2010.

92. “Synthesis of Monodisperse TiO2-Paraffin Core-Shell Nanoparticles for Improved Dielectric Properties,” B. Balasubramanian, K. L. Kraemer, N. A. Reding, R. Skomski, S. Ducharme, D. J. Sellmyer, ACS Nano 4 (4), 1893-1900 (2010).

91. “Ferroelectric Nanocrystals and their switching,” V. M. Fridkin, R. Gaynutdinov, S. Ducharme, PhysicsUspekhi 53 (2), 199-207 (2010); in Russian, Uspekhi Fizicheskikh Nauk 170 (2), 247-262, (2010).

90. “Modeling of metal-ferroelectric-insulator-semiconductor structures based on Langmuir–Blodgett copolymer films,” T. J. Reece, S. Ducharme, J. Appl. Physics 106, 124505 (2009).

89. “Nanoscale Domain Patterns in Ultrathin Polymer Ferroelectric Films,” P. Sharma, T. J. Reece, D. Wu, V. M. Fridkin, S. Ducharme, A. Gruverman, J. Physics: Condensed Matter 21, 485902 (2009).

88. S. Ducharme, ACS Nano 3 (9), 2447–50 (2009). Invited Perspective article.

87. “Polarization switching kinetics of ferroelectric nanomesas of vinylidene fluoride-trifluoroethylene copolymer,” R. V. Gaynutdinov, O. A. Lysova, S. G. Yudin, A. L. Tolstikhina, A. L. Kholkin, V. M. Fridkin, S. Ducharme, Applied Physics Letters 95, 023303 (2009); Virtual Journal of Nanoscale Science and Technology 20 (4), 27 July 2009.

86. “Magnetism of TiO and TiO2 nanoclusters,” X. Wei, R. Skomski, B. Balamurugan, Z. G. Sun, S. Ducharme and D. J. Sellmyer, Journal of Applied Physics 105, 07C517.1-3 (2009).

85. “Start the Presses,” S. Ducharme and A. Gruverman, Nature Materials 8, 9-10 (2009). Invited “News and Views” article. DOI:10.1038/nmat2348

84. "J. Y. Li, Q. G. Du, S. Ducharme, Journal of Applied Physics 104, 094302.1-7 (2008); Virtual J. of Nanoscale Science and Technology 18 (20), 17 November 2008.

83. “Switching Kinetics of Ferroelectric Nanomesas,” C. M. Othon, J. Kim, S. Ducharme, V. M. Fridkin, J. Applied Physics 104, 054109 (2008); Virtual Journal of Nanoscale Science and Technology 18 (12), 22 September 2008.

82. “Oligo(vinylidene fluoride) Langmuir-Blodgett films studied by spectroscopic ellipsometry and the density functional theory,” R. Korlacki, J. T. Johnston, J. Kim, S. Ducharme, D. W. Thompson, V. M. Fridkin, Z. Ge, James M. Takacs, J. Chemical Phys. 129, 064704 (2008).

81. “Local Probing of Relaxation Time Distributions in Ferroelectric Polymer Nanomesas: Time-Resolved Piezoresponse Force Spectroscopy and Spectroscopic Imaging,” B. J. Rodriguez, S. Jesse, J. Kim, S. Ducharme, S. V. Kalinin, Applied Physics Letters 92, 232903.1-3 (2008); Virtual J. of Nanoscale Science and Technology 17 (25), 23 June 2008.

80. “Polarization Switching Kinetics at the Nanoscale in Ferroelectric Copolymer Langmuir-Blodgett Films,” R. V. Gaynutdinov, O. A. Lysova, A. L. Tolstikhina, S. G. Yudin, V. M. Fridkin, and Stephen Ducharme, Applied Physics Letters 92, 172902.1-3 (2008); Virtual Journal of Nanoscale Science and Technology 17 (19), 12 May 2008.

79. “Effects of an external electric field on the ferroelectric-paraelectric phase transition in polyvinylidene fluoride-trifluoroethylene copolymer Langmuir–Blodgett films,” M. Poulsen, A. V. Sorokin, S. Adenwalla, S. Ducharme, V. M. Fridkin, Journal of Applied Physics 103, 113803.1-9 (2008).

78. “Microimprinting and ferroelectric properties of poly(vinylidene fluoride-trifluoroethylene) copolymer films,” L. Zhang, S. Ducharme, J. Y. Li, Applied Phys. Lett. 19, 172906 (2007).

77. “Ferroelectric properties of Langmuir-Blodgett copolymer films at the nanoscale,” A. Tolstousov, R. V. Gaynutdinov, R. Tadros-Morgane, S. G. Yudin, A.L. Tolstikhina, H. Kliem, S. Ducharme, V. M. Fridkin, Ferroelectrics 354, 99-105 (2007).

76. “Electron diffraction study of the structure of vinylidene fluoride-trifluorethylene copolymer nanocrystals” M. Bai, X. Z. Li, S. Adenwalla, M. Poulsen, J. Physics: Condensed Matter 19, 196211 (2007).

75. “The Electric Energy Density of Dielectric Nanocomposites,” J. Y. Li, L. Zhang, S. Ducharme, Applied Physics Letters 90, 132901 (2007); Virtual Journal of Nanoscale Science and Technology 15 (14), 9 April 2007.

74. “Nanoscale polarization manipulation and imaging of ferroelectric Langmuir-Blodgett polymer films,” B. J. Rodriguez, S. Jesse, S. V. Kalinin, J. Kim, S. Ducharme, Applied Physics Letters 90, 132901 (2007).

73. "The Effect of Interlayer Interactions on the Ferroelectric-Paraelectric Phase Transition in Multilayered Thin Films of Vinylidene Fluoride-Trifluoroethylene Copolymers,” J. Kim, H. You, S. Ducharme, S. Adenwalla, J. Physics: Condensed Matter 19, 086206 (2007).

72. “Polyvinylidene fluoride–trifluoroethylene as a reservoir for absorbed water,” P. A. Jacobson, L. G. Rosa, K. Kraemer, S. Ducharme, P. A. Dowben, Materials Letters 31, 1137-41 (2007).

71. “Effects of annealing conditions on ferroelectric nanomesa self-assembly,” M. Bai, M, Poulsen, S. Ducharme, J. Physics: Condensed Matter 18, 7383-92 (2006).

70. “Low-Voltage operation of metal-ferroelectric-insulator-semiconductor diodes incorporating a ferroelectric polyvinylidene fluoride copolymer Langmuir-Blodgett film,” A. Gerber, M. Fitsilis, H. Kohlstedt, R. Waser, T. J. Reece, S. Ducharme, E. Rije, J. Applied Physics 100, 024110 (2006).

69. “A Continuum Model on the Nanomesa and Nanowell Formation in Langmuir-Blodgett Ferroelectric Polymeric Films,” J. Li, Y Luo, M. Bai, S. Ducharme, J. Mechanics and Physics of Solids 54, 2462-82 (2006).

68. “Comparison of the electronic structure of two polymers with strong dipole ordering,” J. Xiao, L. G. Rosa, M. Poulsen, D.-Q. Feng, D. S. Reddy, J. M. Takacs, L. Cai, J. Zhang, S. Ducharme, P. A. Dowben, J Physics: Condensed Matter 18, L155-61 (2006).

67. “Ferroelectric Polymer Langmuir-Blodgett Films for Non-Volatile Memory Applications,” S. Ducharme, T. J. Reece, C. M. Othon, R. K. Rannow, IEEE Transactions on Device and Material Reliability 5, 720-735 (2005).

66. “Nanomesa and Nanowell Formation in Langmuir-Blodgett Polyvinylidene Fluoride Trifluoroethylene Copolymer Films,” J. Li, Y. Luo, M. Bai, S. Ducharme, Applied Physics Letters 87, 213116 (2005); Virtual Journal of Nanoscale Science and Technology 12 (22), 28 November 2005 http://www.vjnano.org.

65. Matt Poulsen, S. Ducharme, A. V. Sorokin, S. Reddy, J. M. Takacs, Y. Wen, J. Kim, S. Adenwalla, Ferroelectrics Letters 32, 85-89 (2005).

64. “The Effect of Humidity on the Dielectric Response in Ferroelectric Polymer Films Made by Langmuir-Blodgett Deposition,” K. L. Kraemer, A. V. Sorokin, C. M. Othon, S. Ducharme, V. M. Fridkin, Ferroelectrics Letters 32, 91-97 (2005).

63. “Comparison of Crystalline Thin Poly(vinylidene (70%) - trifluoroethylene (30%)) Copolymer Films with Short Chain Poly(vinylidene fluoride) film,” J. Choi, E. Morikawa, S. Ducharme, P. A. Dowben, Materials Letters 58, 3599-3603 (2005).

62. “Manifestation of a Ferroelectric Phase Transition in Ultrathin Films of Polyvinylidene Fluoride,” A. R. Geivandov, S. G. Yudin, V. M. Fridkin, S. Ducharme, Physics of the Solid State 47, 1590-94 (2005).

61. “Pyroelectric study of polarization switching in Langmuir-Blodgett films of poly(vinylidene fluoride – trifluoroethylene),” A. V. Sorokin, S. Ducharme, V. M. Fridkin, G. M. Vizdrik, J. Applied Physics 98, 044107.1-10 (2005).

60. “Switching in one Monolayer of the Ferroelectric Polymer,” V. Fridkin, A. Ievlev, K. Verkhovskaya, G. Vizdrik, S. Yudin, S. Ducharme, Ferroelectrics, 214, 37-40 (2005).

59. “Electron irradiation effects on ferroelectric copolymer Langmuir-Blodgett films,” C. Othon and S. Ducharme, J. Applied Physics 98, 014106.1-6 (2005).

58. “The Surface Structure of Ultra-Thin P(VDF-TrFE) Copolymer Films on Graphite,” L. Cai, H. Qu, C. Lu, S. Ducharme, P. A. Dowben, J. Zhang, Phys. Review B 70, 155411 (2004).

57. “Ferroelectric Nanomesa Formation from Polymer Langmuir-Blodgett Films,” M. Bai & S. Ducharme, Applied Physics Letters 85, 3528-30 (2004).

56. “Electron Irradiation Effects on the Switching Behavior of a Ferroelectric Polymer,” Christina M. Othon & S. Ducharme, Ferroelectrics 304, 9-12 (2004).

55. “Mapping Surface Polarization in Thin Films of the Ferroelectric Polymer P(VDF-TrFE),” B. Peterson, S. Ducharme, V. M. Fridkin, T. J. Reece, Ferroelectrics 304, 51-54 (2004).

54. “Simulations of ferroelectric polymer film polarization: the role of dipole interactions,” C.-G. Duan, W. N. Mei, W.-G. Yin, J. Liu, J. R. Hardy, S. Ducharme, P. A. Dowben, Physical Review B 69, 235106.1-6 (2004).

53. Determination of the Optical Dispersion in Ferroelectric Vinylidene Fluoride (70%)/Trifluoroethylene (30%) Copolymer Langmuir-Blodgett Films,” M. Bai, A. V. Sorokin, M. Poulsen, S. Ducharme, C. M. Herzinger, S. P. Palto, S. G. Yudin, V. M. Fridkin, J. Applied Physics 95, 3372-76 (2004).

52. “Ferroelectricity at the Molecular Level,” L. Blinov, A. Bune, P. Dowben, S. Ducharme, V. Fridkin, S. Palto, K. Verkhovskaya, G. Vizdrik, S. Yudin, Phase Transitions 77, 161-73 (2004).

51. “Water absorption and dielectric changes in crystalline poly(vinylidene fluoride-trifluoroethylene) copolymer films,” P. A. Jacobson, L. G. Rosa, C.M. Othon, K.L. Kraemer, A.V. Sorokin, S. Ducharme, P.A. Dowben, Applied Phys. Lett. 84, 88-90 (2004).

50. “Kinetics of Intrinsic Ferroelectric Switching in Ultrathin Films,” G. Vizdrik, S. Ducharme, V. M. Fridkin, S. G. Yudin, Physical Review B 68, 094113.1-6 (2003).

49. “Theoretical study on the optical properties of polyvinylidene fluoride crystal,” C.-G. Duan, W. N. Mei, W.-G. Yin, J. Liu, J. R. Hardy, M. Bai, S. Ducharme, P. A. Dowben, J. Physics: Condensed Matter 15, 3805-11 (2003).

48. “Infrared Spectroscopic Ellipsometry of Vinylidene Fluoride (70%) Trifluoroethylene (30%) Copolymer Langmuir-Blodgett Films,” M. Bai, M. Poulsen, A. V. Sorokin, S. Ducharme, D. W. Thompson, C. M. Herzinger, V. M. Fridkin, J. Applied Physics 94, 195-200 (2003).

47. “Nanoscale Polarization Manipulation and Conductance Switching in Ultra Thin Ferroelectric Copolymer Films: P(VDF-TrFE),” H. Qu, W. Yao, T. Garcia, J. Zhang, A.V. Sorokin, S. Ducharme, P.A. Dowben, V.M. Fridkin, Applied Phys. Lett. 82, 4322-4 (2003).

46. “Nonvolatile Memory Element Based on a Ferroelectric Polymer Langmuir-Blodgett Film,” T. J. Reece, S. Ducharme, A. V. Sorokin, M. Poulsen, Applied Physics Letters, 142-44 (2003).

45. “Comparison of the Theoretical and Experimental Band Structure of Poly(vinylidene fluoride) Crystal,” C.-G. Duan, W. N. Mei, J. Liu, J. R. Hardy, S. Ducharme, J. Choi, P. A. Dowben, Europhysics Letters 61, 81-87 (2003).

44. “Heterojunction Diode Fabrication from Polyaniline and a Ferroelectric Polymer,” B. Xu, Y. Ovchenkov, M. Bai, A.N. Caruso, A.V. Sorokin, S. Ducharme, B. Doudin, P.A. Dowben, Applied Physics Letters 81, 4281-3 (2002).

43. “Langmuir-Blodgett Films of Polyethylene,” A. V. Sorokin, M. Bai, S. Ducharme, M. Poulsen, J. Applied Physics 92, 5977-81 (2002).

42. “Dielectric Properties of a Ferroelectric Copolymer Langmuir-Blodgett Film,” M. S. Jogad & S. Ducharme, Current Science (India) 83, 472-476 (2002).

41. “Multilayered Ultrathin Ferroelectric Langmuir-Blodgett Films,” T. M. Batirov, S. Ducharme, V. M. Fridkin, N. Kuznetsova, S. P. Palto, K. A. Verkhovskaya, Integrated Ferroelectrics 37, 155-62 (2001).

40. “General Features of the Intrinsic Coercive Field,” V. M. Fridkin and S. Ducharme, Physics of the Solid State 43, 1320-1324 (2001). (Fizika Tverdogo Tela 43, 1268-71.)

39. “Mesoscopic Structures in Two-Dimensional Ferroelectric Polymers,” S. Ducharme, M. Bai, Matt Poulsen, S. Adenwalla, S. P. Palto, L. M. Blinov, V. M. Fridkin, Ferroelectrics 252, 191-199 (2001).

38. “Aluminum Doping of Poly(vinylidene fluoride with Trifluoroethylene) Copolymer,” B. Xu, C. N. Borca, S. Ducharme, A. V. Sorokin, P. A. Dowben, V. M. Fridkin, S. P. Palto, N. Petukhova, S. G. Yudin, J. Chemical Physics 114, 1866-1869 (2001).

37. “Two-Dimensional Ferroelectrics,” L. M. Blinov, V. M. Fridkin, S. P. Palto, A. V. Bune, P. A. Dowben, S. Ducharme, Physics Uspekhi 170, 243-257 (2000). (Russian, Uspekhi Fizicheskikh Nauk 170, 247-262.) Invited Review.

36. “Two-Dimensional Ferroelectrics,” V. M. Fridkin, S. Ducharme, A. V. Bune, S. P. Palto, S. G. Yudin, L. M. Blinov, Ferroelectrics 236, 1-10 (2000).

35. “Phase Transition in the Surface Structure in Copolymer Films of Vinylidene Fluoride (70%) with Trifluoroethylene (30%),” J. Choi, C. N. Borca, P. A. Dowben, A. V. Bune, S. Pebley, S. Adenwalla, L. Robertson, S. Ducharme, V. M. Fridkin, S. P. Palto, N. Petukhova, S. G. Yudin, Physical Review B 61, 5760-5770 (2000).

34. “Intrinsic Ferroelectric Coercive Field,” S. Ducharme, V. M. Fridkin, A. V. Bune, S. P. Palto, L. M. Blinov, N. N. Petukhova, S. G. Yudin, Physical Review Lett. 84, 175-8 (2000).

33. “Lattice-Stiffening Transition in Copolymer Films of Vinylidene Fluoride (70%) with Trifluoroethylene (30%),” C.N. Borca, S. Adenwalla, J. Choi, P.T. Sprunger, S. Ducharme, L. Robertson, S. P. Palto, J. Liu, Matt Poulsen, V. M. Fridkin, H. You, P. A. Dowben, Physical Review Letters 83, 4562-65 (1999).

32. “Piezoelectric and Pyroelectric Properties of Ferroelectric Langmuir-Blodgett Polymers,” A. V. Bune, C. Zhu, S. Ducharme, L. M. Blinov, V. M. Fridkin, S. P. Palto, N. N. Petukhova, S. G. Yudin, J. Applied Physics 85, 7869-7873 (1999).

31. “Effect of Dipolar Molecules on Carrier Mobilities in Photorefractive Polymers,” A. Goonesekera S. Ducharme, J. Applied Physics 85, 6506-14 (1999).

30. “Influence of Dynamical Scattering in Crystalline Poly(vinylidene fluoride-trifluoroethylene) Copolymers,” C. N. Borca, J. Choi, S. Adenwalla, S. Ducharme, P. A. Dowben, L. Robertson, V. M. Fridkin, S. P. Palto, N. Petukhova, Applied Physics Letters 74, 347-349 (1999).

29. “Evidence of Dynamic Jahn-Teller Distortions in Two-Dimensional Crystalline Molecular Films,” J. Choi, P. A. Dowben, C. N. Borca, S. Adenwalla, A. V. Bune, S. Ducharme, V. M. Fridkin, S. P. Palto, N. Petukhova, Physical Review B 59, 1819-1824 (1999).

28. “Lattice and Electronic Band Structure Changes Across the Surface Ferroelectric Transition,” J. Choi, P. A. Dowben, S. Ducharme, V. M. Fridkin, S. P. Palto, N. Petukhova, S. G. Yudin, Physics Letters A 249, 505-511 (1998).

27. “Measurement of the Photorefractive Grating Phase Shift in a Polymer Using an AC Phase Modulation Technique,” M. Liphardt and S. Ducharme, J. Optical Society of America B 15, 2154-60 (1998).

26. “Two-Dimensional Ferroelectric Films,” A. Bune, V. M. Fridkin, S. Ducharme, L. M. Blinov, S. P. Palto, A. Sorokin, S. G. Yudin, A. Zlatkin, Nature 391, 874-877 (1998).

25. “Changes in Metallicity and Electronic Structure Across the Surface Ferroelectric Transition of Ultra Thin Crystalline poly(vinylidene flouride-triflouroethylene) Copolymers,” J. Choi, P. A. Dowben, S. Pebley, A.V. Bune, S. Ducharme, V. M. Fridkin, S. P. Palto, N. Petukhova, Physical Review Letters 80, 1328-31 (1998).

24. “Critical Point in Ferroelectric Langmuir-Blodgett Polymer Films,” S. Ducharme, A. V. Bune, V. M. Fridkin, L. M. Blinov, S. P. Palto, A. V. Sorokin, S. Yudin, Physical Review B 57, 25-28 (1998).

23. “Low-Field Hole Mobility in a Photorefractive Polymer,” A. Goonesekera, S. Ducharme, J. M. Takacs, L. Zhang, J. Chemical Physics 107, 8709-8712 (1997).

22. “Ultrathin Ferroelectric Polymer Films,” S. Ducharme, A. Bune, V. M. Fridkin, L. M. Blinov, S. P. Palto, N. Petukhova, S. G. Yudin, Ferroelectrics 102, 29-37 (1997).

21. “Effect of Absorption on Photorefractive Grating Decay Curves,” M. Liphardt, S. Ducharme, A. Goonesekera, J. M. Takacs, L. Zhang, J. of the Optical Society of America B 13, 2252-2260 (1996).

20. “Novel Switching Phenomena in Ferroelectric Langmuir-Blodgett Films,” A. Bune, S. Ducharme, V. M. Fridkin, L. Blinov, S. Palto, N. Petukhova, S. Yudin, Applied Physics Letters, 67, 3975-3977 (1995).

19. “Intensity-Dependent Asymmetric Transmission Through a Photorefractive Fabry-Perot Étalon,” S. Ducharme, Bao Vu, Ferroelectrics 174, 197-209 (1995).

18. “Photoconductivity and Grating Response Time of a Photorefractive Polymer,” B. E. Jones, S. Ducharme, M. Liphardt, A. Goonesekera, J. M. Takacs, L. Zhang, R. V. Athalye, J. of the Optical Society of America B 11, 1064-1072 (1994).

17. “High Performance Photorefractive Polymers,” M. Liphardt, A. Goonesekera, B. E. Jones, S. Ducharme, J. M. Takacs, L. Zhang, Science 263, 367-369 (1994).

16. “Electric-Field-Stabilization and Competition of Gratings in a Photorefractive Polymer,” S. Ducharme, B. Jones, J. M. Takacs, L. Zhang, Optics Letters 18, 152-154 (1993).

15. “Pyro-Electro-Optic Phase Gratings,” S. Ducharme, Optics Letters 16, 1791 (1991). “Erratum,” Optics Letters 17, 459-461 (1992).

14. “Observation of the Photorefractive Effect in a Polymer,” S. Ducharme, R. W. Twieg, J. C. Scott, W. E. Moerner, Physics Review Letters 66, 1846-1849 (1991).

13. “Intracavity Frequency Doubling of a Nd:YAG Laser With an Organic Nonlinear Optical Crystal,” S. Ducharme, W. P. Risk, W. E. Moerner, V. Y. Lee, R. W. Twieg, G. C. Bjorklund, Applied Physics Letters 57, 537 (1990).

12. “Photodarkening Profiles and Kinetics in Chalcogenide Glasses,” S. Ducharme, J. Hautala, P. C. Taylor, Physics Review B 41, 12250 (1990).

11. “Nonlinear Optical Studies of Polysilanes,” P. Shukla, P. M. Cotts, R. D. Miller, S. Ducharme, R. Astana, J. Zavislan, Molecular Crystals and Liquid Crystals 183, 241 (1990).

10. “Absorption at Radio and Microwave Frequencies in Superconducting Perovskites,” S. Ducharme, R. Durny, J. Hautala, D. J. Zheng, O. G. Symko, P. C. Taylor, S. Kulkarni, J. Applied Physics 66, 1252 (1989).

9. “Microwave-Induced Voltages in Superconducting Y-Ba-Cu-O,” R. Durny, S. Ducharme, J. Hautala, D. J. Zheng, O. G. Symko, P. C. Taylor, S. Kulkarni, Physica C 162, 1065 (1989).

8. “Absorption of Microwaves in Superconducting Y1Ba2Cu3O7:A Field-Cooling Study,” R. Durny, S. Ducharme, J. Hautala, D. J. Zheng, O. G. Symko, P. C. Taylor, S. Kulkarni, J. of the Optical Society of America B 6, 465 (1989).

7. “Dissipative Flow of Josephson and Abrikosov Fluxons in High Tc Superconductors,” O.G. Symko, D.J. Zheng, R. Durny, S. Ducharme, P.C. Taylor, Physics Letters A 134, 72 (1988).

6. “Microwave Absorption in the Superconducting and Normal Phases of Y1Ba2Cu3O7,” R. Durny, J. Hautala, S. Ducharme, B. Lee, O. G. Symko, P. C. Taylor, D. J. Zheng, J. A. Xu, Physics Review B 36, 2361 (1987).

5. “Absorption in Amorphous Silicon Doping-Modulated Multilayers,” R. Durny, S. Ducharme, J.M. Viner, P.C. Taylor, D. Haneman, J. Non-Crystalline Solids 97, 927 (1987).

4. “Electro-optic and Piezoelectric Measurements in Photorefractive Barium Titanate and Strontium Barium Niobate,” S. Ducharme, J. Feinberg, R. Neurgaonkar, J. of Quantum Electronics 23, 2116 (1987).

3. “Altering the Photorefractive Properties of BaTiO3 by Reduction and Oxidation at 650°C,” S. Ducharme and Jack Feinberg, J. of the Optical Society of America A 3, 283 (1986).

2. “Speed of the Photorefractive Effect in a BaTiO3 Single Crystal,” S. Ducharme and J. Feinberg, J. of Applied Physics 56, 839 (1984).

1. “Thermal Propagation and Stability in Superconducting Films,” K. E. Gray, R. T. Kampwirth, J. F. Zasadzinski, S. Ducharme, J. of Physics F:Metal Physics 13, 404 (1983).

Book Chapters

1. “Ferroelectric Polymer Langmuir-Blodgett Films,” S. Ducharme, S. P. Palto, V. M. Fridkin, L. M. Blinov, Ch. 11 in Ferroelectric and Dielectric Thin Films, Vol. 3 of Handbook of Thin Films Materials, Hari Singh Nalwa, ed. (Academic Press, San Diego, 2002).

Patents

5. “System and method for improving data acquisition capability in spectroscopic rotatable element, rotating element, modulation element, and other ellipsometer and polarimeter and the like systems,” S. E. Green, C. M. Herzinger, B. D. Johs, J. A. Woollam, S. P. Ducharme. US Patent #5,956,145 issued 21 September 1999. Assignee: J. A. Woollam Co. Inc.

4. “Ellipsometer,” S. P. Ducharme, E. H. Machlab, B. D. Johs, J. A. Woollam, UNL and J. A. Woollam Company. U. S. Patent #5,657,126 issued 12 August 1997. Assignee: The Board of Regents of the University of Nebraska.

3. “Photorefractive Materials,” S. P. Ducharme, W. E. Moerner, J. C. Scott, R. W. Twieg. U. S. Patent #5,460,907 issued 24 October 1995; Continuation Patent #5,460,907, issued 24 October 1995. Assignee: IBM Corporation.

2. “Small Modulation Ellipsometer,” S. P. Ducharme, E. H. Machlab, B. D. Johs, J. A. Woollam, UNL and J. A. Woollam Company. U. S. Patent #5,416,588 issued 16 May 1995. Assignee: The Board of Regents of the University of Nebraska.

1. “Photorefractive Materials,” S. P. Ducharme, W. E. Moerner, J. C. Scott, R. W. Twieg. U. S. Patent #5,064,264 issued 12 November 1991; European patent #91309082.5, issued 11 November 1991. Assignee: IBM Corporation.

 

Recent Graduates

Jihee Kim, Ph.D., 2008. "Polarization Coupling in Nanostructured Ferroelectric Polymer Langmuir-Blodgett Films"
Timothy J. Reece, Ph.D., 2007. "Characterization of Metal-Ferroelectric-Insulator-Semiconductor Structures Based on Ferroelectric Langmuir-Blodgett Polyvinyidene Fluoride Copolymer Films for Nondestructive Random Access Memory Applications"
Matt Poulsen, Ph.D., 2007. "Investigation of Ferroelectric Behavior in Electroactive Polymer Systems"
Christina Othon, Ph.D. 2005. "Switching Dynamics of Ferroelectric Langmuir-Blodgett Copolymer Films"
Brad Peterson, B.S., 2004. "Pyroelectric Scanning Microscopy"
Menjun Bai, Ph.D. 2002. "Structure of Ferroelectric Polymer PVDF/TrFE Copolymer Langmuir-Blodgett Films"

Active Collaborations

Active Collaborations:
Vladimir Fridkin (Institute of Crystallography, Russian Academy of Science, Moscow); James M. Takacs (UNL Department of Chemistry); Shireen Adenwalla Axel Enders, Alexei Gruverman, and David Sellmyer (UNL Department of Physics and Astronomy); Jinsong Huang (UNL Department of Mechanical Engineering); Yongfeng Lu (UNL Department of Electrical Engineering); Serge Nakhmanson (Argonne National Laboratory); Herman Kohlstedt (U. of Kiel, Germany). 

Outreach

UNL Speakers Bureau; NCMN Outreach and Education Chair

 

Current Group Members:

Kristin Kraemer, Shashi Poddar, Jingfeng Song (Graduate students)
Susan Cooper, Mitchell Schmidt, Ben Wotruba (Undergraduate Student)
Steven Wignall, Seward HS teacher (summers)
Nicholas Reding, Papillion-La Vista HS teacher (summers)