Recent Publications

  1. “Interplay of broken symmetry and delocalized excitations in the insulating state of 1T-TaS2”, Xun Jia1, Anubhab Haldar, Jungho Kim, Yilin Wang, Gilberto Fabbris, Karl Ludwig, Stefanos Kourtis, Mary Upton, Yu Liu, Wenjian Lu, Xuan Luo, Yu-Ping Sun, Diego Casa, Sahar Sharifzadeh, Pierre T. Darance, Yue Cao, arXiv: 2210.01181 (2023), Phys. Rev. B, in press.
  2. “X-ray and Molecular Dynamics Study of the Temperature-Dependent Structure of FLiNaK”, Jicheng Guo*, Yifan Zhang*, Karl Ludwig*, Haoxuan Yan, Alexander Levy, Anubhav, Wadehra, Michael Gao, Chris Benmore, Melissa Rose, Nicholas Condon, Adam Powell, Yu Zhong and Uday Pal (* contributing equally). Nucl. Mater. Energy 37, 101530 (2023).
  3. “Local Step-Flow Dynamics in Thin Film Growth with Desorption”, Xiaozhi Zhang, Jeffrey G. Ulbrandt, Peco Myint, Andrei Fluerasu, Lutz Wiegart, Yugang Zhang, Christie Nelson, Karl F. Ludwig and Randall L. Headrick, Phys. Rev. Mater., in press. arXiv:2305.18661.
  4. “Influence of plasma species on the early-stage growth kinetics of epitaxial InN grown by plasma-enhanced atomic layer deposition”, Jeffrey Woodward, Samantha Rosenberg, David Boris, Michael Johnson, Scott Walton, Scooter Johnson, Zachary Robinson, Neeraj Nepal, Karl F. Ludwig, Jr., Jennifer Hite, and Charles (Chip) Eddy Jr., J. of Vac. Sci. Technol. A 40, 062405 (2022). Chosen as an Editor’s Pick.
  5. “Early Stage Growth of Amorphous Thin Film: Average Kinetics, Nanoscale Dynamics and Pressure Dependence”, Chenyu Wang, Karl F. Ludwig, Christa Wagenbach, Meliha G. Rainville, Suresh Narayanan, Hua Zhou, Jeffrey G. Ulbrandt, Randall L. Headrick, arXiv: 2111.14285 (2021), Phys. Rev. Mater. 6, 045601 (2022).
  6. “In Situ GISAXS Observation of Ion-Induced Nanoscale Pattern Formation on Crystalline Ge(001) in the Reverse Epitaxy Regime”, Denise Erb, Peco Myint, Kenneth Evans-Lutterodt, Karl Ludwig and Stefan Facsko, Phys. Rev. B 104, 235434 (2021).
  7. “Nanoscale dynamics during self-organized ion beam patterning of Si: II. Kr+ Bombardment”, Peco Myint, Karl F. Ludwig, Jr., Lutz Wiegart, Yugang Zhang, Andrei Fluerasu, Xiaozhi Zhang, Randall L. Headrick, arXiv: 2007.12294 (2020), Phys. Rev. B 103, 195424 (2021).
  8. “Nanoscale dynamics during self-organized ion beam patterning of Si: I. Ar+ Bombardment”, Peco Myint, Karl F. Ludwig, Jr., Lutz Wiegart, Yugang Zhang, Andrei Fluerasu, Xiaozhi Zhang, Randall L. Headrick, arXiv: 2007.12253 (2020), Phys. Rev. B 103, 195423 (2021).
  9. “de Gennes Narrowing and the Relationship Between Structure and Dynamics in Self-Organized Ion Beam Nanopatterning”, Peco Myint, Karl F. Ludwig, Jr., Lutz Wiegart, Yugang Zhang, Andrei Fluerasu, Xiaozhi Zhang, Randall L. Headrick, arXiv: 2007.07395 (2020), Phys. Rev. Lett. 126, 016101 (2021).
  10. “Probing Subcellular Nanostructure of Engineered Human Cardiomyocytes in 3D Tissue”
    Josh Javor, Jourdan Ewoldt, Paige Cloonan, Anant Chopra, Rebeccah Luu, Guillaume Freychet, Mikhail Zhernenkov, Karl Ludwig, Jonathan Seidman, Christine Seidman, Christopher Chen, David Bishop, Nature MicroNano 7, 10 (2021).
  11. “Measurement of Ehrlich-Schwoebel barrier conntribution to the self-organized formation of ordered surface patterns on Ge(001)”, Peco Myint, Denise Erb, Xiaozhi Zhang, Lutz Wiegart, Yugang Zhang, Andrei Fluerasu, Randall Headrick, Stefan Facsko and Karl F. Ludwig, Jr., arXiv: 2008.06504, Phys. Rev. B 102, 201404(R) (2020).
  12. “Coherent X-rays Measurement of Step-Flow Propagation During Growth on Polycrystalline Thin Film Surfaces”, R.L. Headrick, J.G. Ulbrandt, P. Myint, J. Wan, Y. Li, A. Fluerasu, Y. Zhang, L. Wiegert and K.F. Ludwig, Jr., Nature Communications 10, 2638 (2019).
  13. “Nanoscale Kinetics and Dynamics During Ar+ Patterning of SiO2”, M. Mokhtarzadeh, J.G. Ulbrandt, P. Myint, S. Narayanin, R.L. Headrick and K.F. Ludwig, Jr., Phys. Rev. B 99, 165429 (2019).
  14. “Influence of Temperature on Atomic Layer Epitaxial Growth of Indium Nitride Assessed with In Situ Grazing Incidence Small-Angle X-ray Scattering”, J.M. Woodward, S.G. Rosenberg, A.C. Kozen, N. Nepal, S.D. Johnson, C. Wagenbach, A.H. Rowley, Z.R. Robinson, H. Joress, K.F. Ludwig, Jr. and C.R. Eddy, Jr., J. of Vac. Sci. Technol. A 37, 030901 (2019). Chosen as an Editor’s Pick.
  15. “In-situ Studies of Low Temperature Atomic Level Processing of GaN Surfaces for Atomic Layer Epitaxial Growth”, S.G. Rosenberg, C. Wagenbach, V.R. Anderson, S.D. Johnson, N. Nepal, A.C. Kozen, J. Woodward, Z. Robinson, M. Munger, H. Joress, K.F. Ludwig and C.R. Eddy, Jr., J. of Vac. Sci. Technol. A 37, 020928 (2019).
  16. “Low Temperature Surface Preparation of GaN Substrates for Atomic Layer Epitaxial Growth: Assessment of Ex Situ Preparations”, S.G. Rosenberg, D.J. Pennachio, C. Wagenbach, S.D. Johnson, N. Nepal, A.C. Kozen, J. Woodward, Z. Robinson, H. Joress, K.F. Ludwig, C.J. Palmstrom, C.R. Eddy, Jr., J. of Vac. Sci. Technol. A 37, 020908 (2019).
  17. “Understanding the Effect of Nitrogen Plasma Exposure on Plasma Assisted Atomic Layer Epitaxy of InN Monitored by Real Time Grazing-Incidence Small-Angle X-ray Scattering”, N. Nepal, V.R. Anderson, S.D. Johnson, B.P. Dowoney, D.J. Meyer, Z.R. Robinson, J.M. Woodward, K.F. Ludwig, Jr. and C.R. Eddy, Jr., J. of Vac. Sci. Technol. A 37, 020910 (2019). Chosen as an Editor’s Pick.
  18. “Measurement of Bulk Oxygen Diffusivity in (La0.8S0.2)0.95MnO3±d”, J. Davis, U. Pal, S. Gopalan, K. Ludwig and S. Basu, JOM 71, 96 (2019).
  19. “Sawtooth Structure Formation Under Nonlinear-Regime Ion Bombardment”, J. Perkinson, J. Swenson, A. DeMasi, C. Wagenbach, K. Ludwig, S. Norris and M. Aziz, J. Phys.: Condens. Matter 30, 294004 (2018).
  20. “Simulations of Co-GISAXS During Kinetic Roughening of Growth Surfaces”, Mahsa Mokhtarzadeh and Karl Ludwig, J. Synchrotron Rad.24, 1187 (2017).
  21. “Analysis of InGaN Nanodots Grown by Droplet Heteroepitaxy Using Grazing Incidence Small-Angle X-ray Scattering and Electron Microscopy”, J.M. Woodward, A. Yu. Nikiforov, K.F. Ludwig, Jr., and T.D. Moustakas, J. Appl. Phys. 122, 065305 (2017).
  22. “Surface Segregation in Lanthanum Strontium Manganite Thin Films and its Potential Effect on the Oxygen Reduction Reaction”, J.N. Davis, K.F. Ludwig, K.E. Smith, J.C. Woicik, S. Gopalan, U.B. Pal and S.N. Basu, J. Electrochem. Soc. 164, F3091 (2017).
  23. “Distinguishing Physical Mechanisms Using GISAXS Experiments and Linear Theory: The Importance of High Wavenumbers”, S. Norris, J. Perkinson, M. Mokhtarzadeh, E. Anzenberg, M. Aziz and K. Ludwig, Scientific Reports 7, 2016 (2017).
  24. “Characterization of the LCLS ‘Nanosecond Two-Bunch’ Mode for X-ray Speckle Visibility Spectroscopy Experiments”, Y. Sun, D. Zhu, S. Song, F.-J. Decker, M. Sutton, K. Ludwig, W. Roseker, G. Grübel, S. Hruszkewycz, G.B. Stephenson, P.H. Fuoss and A. Robert, Proc. SPIE 10237N, doi.10.1117/12.2265454 (2017).
  25. “Plasma-Assisted Atomic Layer Epitaxial Growth of Aluminum Nitride Studied with Real Time Grazing Incidence Small Angle X-ray Scattering”, V.R. Anderson, N. Nepal, S.D. Johnson, Z.R. Robinson, A. Nath, A.C. Kozen, S.B. Qadri, A. DeMasi, J.K. Hite, K.F. Ludwig and C.R. Eddy, Jr., J. Vac. Sci. Technol. A 35, 031508 (2017).
  26. “Real-time Growth Study of Plasma Assisted Atomic Layer Epitaxy of InN Films by Synchrotron X-ray Methods”, N. Nepal, V.R. Anderson, S.D. Johnson, B.P. Downey, D.J. Meyer, A. DeMasi, Z.R. Robinson, K.F. Ludwig and C.R. Eddy, Jr., J. Vac. Sci. Technol. A 35, 031504 (2017).
  27. “A Case Study of ALD Encapsulation of Quantum Dots: Embedding Supported CdSe/CdS/ZnS Quantum Dots in a ZnO Matrix”, K. Devloo-Casier, P. Geiregat, K. Ludwig, K. Van Stiphout, A. Vantomme, Z. Hens, C. Detavernier, J. Dendooven, J. Phys. Chem. C 120, 18039 (2016).
  28. “Chemical Characterization of Surface Precipitates in La0.7Sr0.3 xCo0.2Fe0.8O3-δ as Cathode Material for Solid Oxide Fuel Cells”, Y. Yu, A. Nikiforov, T. Kasper, J. Woicik, K.F. Ludwig, S. Gopalan, U. Pal and S. Basu, Journal of Power Sources 333, 247 (2016).
  29. “Effect of Sr Content and Strain on Sr Surface Segregation of La1-xSrxCo0.2Fe0.8O3-δ as Cathode Material for Solid Oxide Fuel Cells, Y. Yu, K.F. Ludwig, J.C. Woicik, S. Gopalan, U. Pal, T.C. Kaspar and S.N. Basu, ACS Applied Materials and Interfaces 8, 26704 (2016).
  30. “Using Coherent X-rays to Directly Measure the Propagation Velocity of Defects During Thin Film Deposition”, Jeffrey G. Ulbrandt, Meliha G. Rainville, Christa Hoskin, Suresh Narayanan, Alec R. Sandy, Hua Zhou, Karl F. Ludwig, Jr. and Randall L. Headrick, Nature Physics 12, 794 (2016).
  31. “Co-GISAXS as a New Technique to Investigate Surface Growth Dynamics”, M.G. Rainville, C. Hoskin, J.G. Ulbrandt, S. Narayanan, A.R. Sandy, H. Zhou, R.L. Headrick and K.F. Ludwig, Jr., Phys. Rev. B 92, 214102 (2015).
  32. “Vacancy Assisted SrO Formation on La0.8Sr0.2Co0.2 Fe0.8O3– Surfaces – A Synchrotron Photoemission Study”, J. Kuyyalil, D. Newby, Jr., J. Laverock, Y. Yu, D. Cetin, S. Basu, K. Ludwig and K.E. Smith, Surf. Sci. 642, 33 (2015).
  33. “Surface Evolution of Lanthanum Strontium Cobalt Ferrite Thin Films at Low Temperatures”, D. Newby Jr., J. Kuyyalil, J. Laverock, K.F. Ludwig, Y. Yu, J. Davis, S. Gopalan, U. Pal, S. Basu and K.E. Smith, Thin Solid Films 589, 655 (2015).
  34. “Ion beam nanopatterning of III-V semiconductors: consistency of experimental and simulation trends within a chemistry-driven theory”, O. El-Atwani, S. Norris, K. Ludwig, S. Gonderman and J.P. Allain, Scientific Reports 5, 18207 (2015).
  35. “Real-Time X-ray Studies of Indium Island Growth Kinetics”, A. DeMasi, M. Rainville and K.F. Ludwig, J. Vac. Sci. and Technol. A 33, 021406 (2015).
  36. “Atomic Layer Deposition-Based Tuning of the Pore Size in MesoPorous Thin Films Studied by In Situ Grazing Incidence Small Angle X-ray Scattering”, J. Dendooven, K. Devloo-Casier, M. Ide, K. Grandfield, M. Kurttepeli, K.F. Ludwig, S. Bals, P. Van Der Voort and C. Detavernier, Nanoscale 6, 14991 (2014).
  37. “Predicting Oxygen Vacancy Non-Stoichiometric Concentration in Perovskites from First Principles”, Heng Luo, Yongwoo Shin, Yang Yu, Deniz Cetin, Karl Ludwig, Uday Pal, Soumendra N. Basu, Srikanth Gopalan, Xi Lin, Appl. Surf. Sci. 323, 65 (2014).
  38. “Model-Independent Test of the Crater Function Theory of Surface Morphology Evolution during Ion Bombardment”, E. Anzenberg, J. Perkinson, M. Aziz and K. Ludwig, Phys. Rev. B 89, 115433 (2014).
  39. “Effect of Atmospheric CO2 on Surface Segregation and Phase Formation in La0.6Sr0.4Co0.2Fe0.8O3-d Thin Films”, Yang Yu, Heng Luo, Deniz Cetin, Xi Lin, Karl Ludwig, Uday Pal, Srikanth Gopalan, Soumendra Basu, Appl. Surf. Sci. 323, 71 (2014).
  40. “Effect of Carbon Dioxide on the Cathodic Performance of Solid Oxide Fuel Cells”, Y. Yu, H. Luo, D. Cetin, X. Lin, K. Ludwig, S. Basu, U. Pal, S. Gopalan, ECS Trans. 61, 131 (2014).
  41. “In-Situ Synchrotron Based X-ray Techniques as Monitoring Tools for Atomic Layer Deposition – A Review”, K. Devloo-Casier, K.F. Ludwig, C. Detavernier and J. Dendooven, J. Vac. Sci Technol. A 32, 010801 (2014).
  42. “Atomic Layer Deposition of TiO2 on Surface Modified Nanoporous Low-k Films”, E. Levrau, K. Devloo-Casier, J. Dendooven, K. Ludwig, P. Verdonck, J. Meersschaut, M. Baklanov and C. Detavernier, Langmuir 29, 12284 (2013).
  43. “Nanopatterning of Metal-Coated Si Surfaces via Ion Beam Irradiation: Real Time X-ray Studies Reveal the Effect of Silicide Bonding”, O. El-Atwani, A. Suslova, A. DeMasi, S. Gonderman, J. Fowler, M. El-Atwani, K. Ludwig and J.P. Allain, J. Appl. Phys.113, 124305 (2013).
  44. “Development of AlGaN-Based Graded-Index-Separate-Confinement Heterostructure Deep UV Emitters by Molecular Beam Epitaxy”, H. Sun, J. Woodward, J. Yin, A. Moldawer, E. Pecora, A. Nikiforov, L. Dal Negro, R. Paiella, K. Ludwig, D. Smith and T.D. Moustakas, J. Vac. Sci. Technol. B 31, 03C117-1 (2013).
  45. “Real Time X-ray Studies during Nanostructure Formation on Silicon via Low Energy Ion Beam Irradiation using Ultrathin Iron Films”, Osman El-Atwani, Anastassiya Suslova, Alexander DeMasi, Sean Gonderman, Justin Fowler, Mohamad El-Atwani, Karl Ludwig, and Jean Paul Allain, Appl. Phys. Lett. 101, 263104 (2012).
  46. “Nanoscale Surface Pattern Formation Kinetics on Germanium Irradiated by Kr+ Ions”, E. Anzenberg, J.C. Perkinson, C.S. Madi, M.J. Aziz and K.F. Ludwig, Jr., Phys. Rev. B 86, 245412 (2012).
  47. “High Contrast X-ray Speckle from Atomic-Scale Order in Liquids and Glasses”, S. Hruszkewycz, M. Sutton, P. Fuoss, B. Adams, S. Rosenkranz, K.F. Ludwig, W. Roseker, D. Fritz, M. Cammarata, D. Zhu, S. Lee, H. Lemke, C. Gutt, A. Robert, G. Gruebel and G.B. Stephenson, Phys. Rev. Lett. 109, 185502 (2012).
  48. “Evidence for Family-Meakin Dynamical Scaling in Island Growth and Coalescence during Vapor Phase Deposition”, Leyla Çolakerol Arslan, Christopher Sanborn, Eitan Anzenberg and Karl F. Ludwig, Jr., Phys. Rev. Lett. 109, 106102 (2012).
  49. “Composition Dependent Bilayer Atomic Ordering in AlxGa1-xN Films Examined by Polarization-Dependent Extended X-ray Absorption Fine Structure”, J.C. Woicik, K.F. Ludwig, Jr. and T.D. Moustakas, Appl. Phys. Lett.100, 162105 (2012).