Publications
P. H. Rekemeyer, S. Chang, C.-H. Chuang, G. W. Hwang, M. G. Bawendi, S. Gradečak, "Enhanced Photocurrent in PbS Quantum Dot Photovoltaics via ZnO Nanowires and Band Alignment Engineering ", Advanced Energy Materials 6, 1600848 (2016).
Y. Song, S. Chang, S. Gradečak, J. Kong, "Visibly-Transparent Organic Solar Cells on Flexible Substrates with All-Graphene Electrodes ", Advanced Energy Materials 6, 1600847 (2016).
V. Steinmann, R. Chakraborty, P. H. Rekemeyer, K. Hartman, R. E. Brandt, A. Polizzotti, C. Yang, T. Moriarty, S. Gradečak, R. G. Gordon, T. Buonassisi, “A two-step absorber deposition approach to overcome shunt losses in thin film solar cells ”, ACS Applied Materials & Interfaces 8 , 22664 (2016).
K. Bogaert, S. Liu, J. Chesin, D. Titow, S. Gradečak, S. Garaj, "Diffusion-Mediated Synthesis of MoS2/WS2 Lateral Heterostructures ", Nano Letters 16 , 5129 (2016).
W. J. Jo, J. T. Nelson, S. Chang, V. Bulović, S. Gradečak, M. S. Strano, K. K. Gleason, "Oxidative Chemical Vapor Deposition of Neutral Hole Transporting Polymer for Enhanced Solar Cell Efficiency and Lifetime ", Advanced Materials 28 , 6399 (2016).
S. Chang, G. Ddeul Han, J. G. Weis, H. Park, O. Hentz, Z. Zhao, T. M. Swager, S. Gradečak, "Transition metal-oxide free perovskite solar cells enabled by a new organic charge transport layer ", ACS Applied Materials & Interfaces 8 , 8511 (2016).
O. Hentz, Z. Zhao, and S. Gradečak, "Impacts of ion segregation on local optical properties in mixed halide perovskite films ", Nano Letters 16 , 1485 (2016).
J. J. Cheng, S. M. Nicaise, K. K. Berggren, and S. Gradečak, "Dimensional tailoring of hydrothermally grown zinc oxide nanowire arrays ", Nano Letters 16 , 753 (2016).
G. Bertoni, F. Fabbri, M. Villani, L. Lazzarini, S. Turner, G. V. Tendeloo, D. Calestani, S. Gradečak, A. Zappetiini, G. Salviati, "Nanoscale maping of plasmon and exciton in ZnO tetrapods coupled with Au nanoparticles ",Scientific Reports 6 , 19168 (2016).
M.-Y. Lu, C.-Y. Tsai, H.-A. Chen, Y.-T. Liang, K.-P. Chen, S. Gradečak, S. Gwo, L.-J. Chen, "Plasminic enhancement of Au nanoparticle-embedded single-crystalline nanowire dye-sensitized solar cells ", Nano Energy 20 , 264 (2016).
B. Franta, D. Pastor, H. H. Gandhi, P. H. Rekemeyer, S.Gradečak, M. J. Aziz, E. Mazur, "Simultaneous high crystallinity and sub-bandgap optical absorptance in hyperdoped black silicon using nanosecond laser annealing ", Journal of Applied Physics 118 , 225303 (2015).
S. Joglekar, M. Azize, E. J. Jones, S. Gradečak, T. Palacios,"Impact of Al2 O3 passivation on GaN-based high electron mobility transistors ", IEEE Transactions on Electron Devices 63 , 318 (2015).
E. J. Jones, S. Ermez, S. Gradečak, "Mapping of strain fields in GaAs/GaAsP core-shell nanowires with nanometer resolution ", Nano Letters 15 , 7873 (2015).
S. Crawford, S. Emrez, G. Haberfehlner, E. Jones, S. Gradečak, "Impact of nucleation conditions on diameter modulation of GaAs nanowires ", Nanotechnology 26 , 225604 (2015).
S. Ermez, E. J. Jones, S. C. Crawford, S. Gradečak, "Self-seeded growth of GaAs nanowires by metal-organic chemical vapor deposition ", Crystal Growth & Design 15 , 2768 (2015).
M.-J. Sher, N. Mangan, M. J. Smith, Y.-T. Lin, S. Marbach, T. Schneider, S. Gradečak, M. P. Brenner, E. Mazur, "Femtosecond-laser hyperdoping silicon in an SF6 atmosphere: dopant incorporation mechanis ", Journal of Applied Physics 117 , 125301 (2015).
F. Fabbri, Y.-T. Lin, G. Bertoni, F. Rossi, M. J. Smith, S Gradeča, E. Mazur, G. Salviati, "Origin of the visible emissio of black silicon microstructures ", Applied Physics Letters 107 , 021907 (2015).
X. Zhou, M.-Y. Lu, Y.-J. Lu, E. Jones, S. Gwo, S. Gradečak, "Nanoscale optical properties of InGaN/GaN nanodisk-in-rod heterostructures ", ACS Nano 9 , 2868 (2015).
S. M. Nicaise, J. J. Cheng, A. Kiani, S. Gradečak, K. K. Berggren, "Electron beam lithography templated zinc oxide nanowire arrays for PV purposes ", Nanotechnology 26 , 075303 (2015). See also the LabTalk article .
M. Seita, J.P. Hanson, S. Gradečak, M.J. Demkowicz, "The dual role of coherent twin boundaries in hydrogen embrittlement ", Nature Communications 6 , 6164 (2015).
J. P. Hanson, M. Seita, S. Gradečak, M. J. Demkowicz, "Hydrogen embrittlement behavior in precipitation hardened Ni-base alloys", Corrosion 2015, paper no. 05853 (Dallas, TX: NACE, 2015).
S. Chang, H. Park, J. Cheng, P. Rekemeyer, S. Gradečak, "Improved efficiency in organic/inorganic hybrid solar cells by interfacial modification of ZnO nanowires with small molecules ", Journal of Physics D 47 , 394016 (2014).
H. Park, S. Chang, X. Zhou, J. Kong, T. Palacios, S. Gradečak, "Flexible graphene electrode-based organic photovoltaics with record-high efficiency ", Nano Letters 14 (9), 5148-5154 (2014).
X. Zhou, J. Chesin, S. Gradečak, “GaN nanowire-based lasers” in V. Consonni, G.
Feuillet, Wide band-gap semiconductor nanowires 2: heterostructures and optoelectronic devices , ISTE-Wiley and Hermes Science Publishing. (Sept. 2014)
J.M. Warrender, J. Mathews, D. Recht, M. Smith, S. Gradečak, M.J. Aziz, "Morphological stability during solidification of silicon incorporating metallic impurities ", Journal of Applied Physics 115 , 163516 (2014).
M. Y. Lu, X. Zhou, C. Y. Chiu, S. Crawford, S. Gradečak, “From GaN to ZnGa2 O4 through a low temperature process: nanotube and heterostructure arrays ”, ACS Applied Materials and Interfaces 6 (2), 882–887 (2014).
J. Chesin, S. Gradečak, "Comparing directed efficiency of III-nitride nanowire light emitting diodes ", Journal of Nanophotonics 8 (1), 083095 (2014).
M. J. Smith, M.-J. Sher, B. Franta, Y.-T. Lin, E. Mazur, S. Gradečak, "Improving dopant incorporation during femtosecond-laser doping of Si with a Se thin-film dopant precursor ", Applied Physics A 114 (4), 1009-1016 (2014).
E. Jones, D. Cooper, J.-L. Rouviere, A. Béché, M. Azize, T. Palacios, S. Gradečak, “Towards rapid nanoscale measurement of strain in III-nitride heterostructures ”, Applied Physics Letters 103 , 231904 (2013).
D. Recht, M. J. Smith, S. Charnvanichborikarn, J. T. Sullivan, M. T. Winkler, J. Mathews, J. M. Warrender, T. Buonassisi, J. S. Williams, S. Gradečak, M. J. Aziz, "Supersaturating silicon with transition metals by ion implantation and pulsed laser melting ", Journal of Applied Physics 114 , 124903 (2013).
M. de la Mata, X. Zhou, F. Furtmayr, J. Teubert, S. Gradečak, M. Eickhoff, A. F. i Morral, J. Arbiol, "Bandgap engineering: 0D, 1D and 2D quantum structures in a nanowire" , Journal of Materials Chemistry C 1 , 4300 (2013).
A. Gumennik, L. Wei, G. Lestoquoy, A. M. Stolyarov, X. Jia, P. H. Rekemeyer, M. J. Smith, X. Liang, B. Grena, S. G. Johnson, S. Gradečak, A. F. Abouraddy, J. D. Joannopoulos, Y. Fink, "Silicon-in-silica spheres via axial thermal gradient in-fibre capillary instabilities ", Nature Communications 4 , 2216 (2013)
X. Zhou, M.-Y. Lu, Y.-J. Lu, S. Gwo, S. Gradečak, "Correlation of doping, structure, and carrier dynamics in a single GaN nanorod ", Applied Physics Letters 102 , 253104 (2013).
K. H. Baloch, A. C. Johnston-Peck, K. Kisslinger, E. A. Stach, and S. Gradečak, "Revisiting the “In-clustering” question in InGaN through the use of aberration-corrected STEM and low-loss EELS below the knock-on threshold ", Applied Physics Letters 102 , 191910 (2013).
L. Hu, M. M. Brewster, C. Tang, S.Gradečak, X. Fang, "Heteroepitaxial growth of GaP/ZnS nanocable with superior optoelectronic response ", Nano Letters 13 , 1941 (2013).
G. Haberfehlner, M. J. Smith, J.-C. Idrobo, G. Auvert, M.-J. Sher, M. T. Winkler, E. Mazur, N. Gambacorti, S. Gradecak, P. Bleuet, "Dopant segregation in femtosecond laser-doped silicon revealed by electron tomography ", Microscopy and Microanalysis 19 , 716 (2013).
H. Park, S. Chang, M. Smith, S. Gradečak, J. Kong, "Interface engineering of graphene for universal applications as both anode and cathode in organic photovoltaics ", Nature Scientific Reports 3 , 1581 (2013).
M. S. Wang, J. P. Hanson, S. Gradečak, M. J. Demkowicz, “Cutting apart of γ'' precipitates by dislocations emitted from nanoscale surface notches in Ni-base alloy 725 ", Materials Research Letters 1 , 77 (2013).
J. Jean, S. Chang, P. R. Brown, J. J. Cheng, P. H. Rekemeyer, M. G. Bawendi, S. Gradečak, Vladimir Bulovic, "Nanowire arrays for enhanced photocurrent in quantum dot solar cells ", Advanced Materials 25 , 2790 (2013).
S. Crawford, S. K. Lim, S. Gradečak, “Opportunities and limitations for modulating nanowire diameter via particle-mediated growth ”, Nano Letters 13 , 226-232 (2013).
H. Park, S. Chang, J. Jean, J. J. Cheng, P. T. Araujo, M. Wang, M. Bawendi, M. S. Dresselhaus, V. Bulovic, J. Kong, S. Gradečak, “Graphene cathode-based ZnO nanowire hybrid solar cells ”, Nano Letters 13 , 233-239 (2013). One of the Top 20 Most Read Articles in Nano Letters for January 2013, March and April 2013 and for a 12-month period in April, May, and June 2013.
F. Fabbri, M. J. Smith, D.l Recht, M. J. Aziz, S. Gradečak, G. Salviati, "Depth-resolved cathodoluminescence spectroscopy of silicon supersaturated with sulfur ", Applied Physics Letters 102 , 031909 (2013).
J. Chesin, X. Zhou, S. Gradečak, "Light extraction in individual GaN nanowires on Si for LEDs ", Proceeding of SPIE 8467 , 846703 (2012).
M. J. Smith, M.-J. Sher, B. Franta, Y.-T. Lin, E. Mazur, S. Gradečak, “The origins of pressure-induced phase transformations during the surface texturing of silicon using femtosecond laser irradiation ”, Journal of Applied Physics 112 , 083518 (2012).
E. J. Jones, M. Azize, M. J. Smith, T. Palacios, Silvija Gradečak, "Correlating stress generation and sheet resistance in InAlN/GaN nanoribbon high electron mobility transistors ", Applied Physics Letters 101 , 113101 (2012).
F. Qian, M. Brewster, S.K. Lim, Y. Ling, C. Greene, O. Laboutin, J. Johnson, S. Gradečak, Y. Cao, Y. Li, "Controlled synthesis of AlN/GaN multiple quantum well nanowire structures and their optical properties ", Nano Letters 12 , 3344-3350 (2012).
M. T. Winkler, M.-J. Sher, Y.-T. Lin, M. Smith, H. Zhang, S. Gradečak, E. Mazur, "Studying femtosecond-laser hyperdoping by controlling surface morphology ", Journal of Applied Physics 111, 093511 (2012).
S. K. Lim, S. Crawford, G. Haberfehlner, S. Gradečak, "Controlled modulation of diameter and composition along individual III-V nitride nanowires ", Nano Letters 13 , 331-336 (2013).
M. Brewster, X. Zhou, M. Y. Lu, and S. Gradečak, "The interplay of structure and optical properties in individual ZnO nanostructures ”, invited review article, Nanoscale 4 , 1455 - 1462 (2012). One of the Top 10 most-read Nanoscale articles for 02/2012 .
S. Ren, M. Bernardi, R. R. Lunt, V. Bulovic, J. C. Grossman, S. Gradečak, "Towards efficient carbon nanotube / P3HT solar cells: active layer morphology, electrical and optical properties ", Nano Letters 11 , 5316-5321 (2011). One of the Top 20 Most Read Articles in Nano Letters for 11/2011.
M. Smith, M. Winkler, M.-J. Sher, Y.-T. Lin, E. Mazur, S. Gradečak, "Effects of a thin film dopant precursor on the structure and properties of femtosecond-laser doped silicon ", Applied Physics A 105 , 795-800 (2011).
M. Azize, O. Saadat, A. Hsu, M. Smith, S. Guo, S. Gradečak, T. Palacios, "High electron mobility transistors based on InAlN/GaN nano-ribbons ", IEEE Electron Device Letters 32 , 1680-1682 (2011).
M. Smith, Y.-T. Lin, M.-J. Sher, M. Winkler , E. Mazur, S. Gradečak, "Pressure-induced phase transformations during femtosecond-laser doping of silicon ", Journal of Applied Physics 110, 053524 (2011). Also selected for the Virtual Journal of Ultrafast Science , October 2011.
S. Ren, L.-Y. Chang, S. K. Lim, J. Zhao, M. Smith, N. Zhao, V. Bulovic, M. Bawendi, S. Gradečak, "Inorganic-organic hybrid solar cell: bridging quantum dots to conjugated polymer nanowires ", Nano Letters 11 , 3998-4002 (2011). One of the Top 20 Most Read Articles in Nano Letters for 09/2011, 10/2011, 08/2012 (12-month period).
M. Brewster, M. Y. Lu, S. K. Lim, X. Zhou, M. Smith, and S. Gradečak, "The Growth and Optical Properties of ZnO Nanowalls ," Journal of Physical Chemistry Letters 2 , 1940-1945 (2011).
M. Brewster, X. Zhou, S. K. Lim, and S. Gradečak, "Role of Au in the growth and nanoscale optical properties of ZnO nanowires ," Journal of Physical Chemistry Letters 2 , 586-591 (2011).
S. Ren, N. Zhao, S. C. Crawford, M. J. Tambe, V. Bulovic, and S. Gradečak, "Heterojunction photovoltaics using GaAs nanowires and conjugated polymers ," Nano Letters 11 , 408-413 (2011).
M. J. Tambe, S. Ren, and S. Gradečak, "Effects of gold diffusion on n-Type doping of GaAs nanowires ," Nano Letters 10 , 4584-4589 (2010).
S. Ren, S. K. Lim, and S. Gradečak, "Synthesis and thermal responsiveness of self-assembled gold nanoclusters ," Chemical Communications 46 , 6246-6248 (2010). Featured as the Inside front cover .
S. K. Lim, S. C. Crawford, and S. Gradečak, "Growth mechanism of GaN nanowires: preferred nucleation site and effect of hydrogen ," Nanotechnology 21 , 345604 (2010).
C. -H. Tseng, M. J. Tambe, S. K. Lim, M. J. Smith, and S. Gradečak, "Position controlled nanowire growth through Au nanoparticles synthesized by galvanic reaction ," Nanotechnology 21 , 165605 (2010). Featured as a Lab Talk Article on nanotechweb.org , April 2010
M. J. Tambe, L. F. Allard, and S. Gradečak, "Characterization of core-shell GaAs/AlGaAs nanowire heterostructures using advanced electron microscopy ," Journal of Physics: Conference Series 209 , 012033 (2010).
M. Brewster, O. Schimek, S. Reich, and S. Gradečak, "Exciton-phonon coupling in individual GaAs nanowires studied using resonant Raman spectroscopy ," Phys. Rev. B 80, 201314(R) (2009). Also selected for Virtual Journal of Nanoscale Science and Technology , December 7, 2009.
S. K. Lim, M. Brewster, F. Qian, Y. Li, C. M. Lieber, and S. Gradečak, "Direct correlation between structural and optical properties of III-V nitride nanowire heterostructures with nanoscale resolution ," Nano Letters 9 , 3940-3944 (2009).
X. Fang, Y. Bando, U. K. Gautam,T. Zhai, S. Gradečak, and D. Golberg, "Heterostructures and superlattices in one-dimensional nanoscale semiconductors ," Journal of Materials Chemistry 19 , 5683-5689 (2009).
M. J. Tambe, S. K. Lim, M. J. Smith, L. F. Allard, and S. Gradečak, "Realization of defect-free epitaxial core-shell GaAs/AlGaAs nanowire heterostructures ," Applied Physics Letters 93 , 15197 (2008). Also selected for Virtual Journal of Nanoscale Science and Technology , November 3, 2008.
S. K. Lim, M. J. Tambe, M. M. Brewster, and S. Gradecak, "Controlled growth of ternary alloy nanowires using metalorganic chemical vapor deposition ," Nano. Lett .8 , 1386-1392 (2008).
F. Qian, Y. Li, S. Gradečak, H. G. Park, Y. Dong, Y. Ding, Z. L. Wang, and C. M. Lieber, "Multi-quantum-well nanowire heterostructures for wavelength-controlled lasers ," Nature Materials 7 , 701-706 (2008).
Y. Li, J. Xiang, F. Qian, S. Gradečak, Y. Wu, H. Yan, D. A. Blom, and C. M. Lieber, "Dopant-free GaN/AlN/AlGaN Radial nanowire heterostructures as high electron mobility transistors ", Nano. Lett . 6 , 1468-1473 (2006).
S. Gradečak, F. Qian, Y. Li, H. G. Park, and C. M. Lieber, "GaN nanowire lasers with low lasing thresholds ", Appl. Phys. Lett. 87 , 173111 (2005).
F. Qian, S. Gradečak, Y. Li, C. Y. Wen, C. M. Lieber, "Core/multishell nanowire heterostructures as multicolor, high-efficiency light-emitting diodes " Nano. Lett . 5 , 2287-2291 (2005)
P. V. Radovanovic, C. J. Barrelet, S. Gradečak, F. Qian, and C. M. Lieber, "General synthesis of manganese-doped II-VI and III-V semiconductor nanowires ", Nano Lett., 5 , 1407-1411 (2005).
B. Lukic, J. W. Seo, E. Couteau, K. Lee, S. Gradečak, R. Berkecz, K. Hernadi, S. Delpeux, T. Cacciaguerra, F. Béguin, A. Fonseca, J. B. Nagy, G. Csányi, A. Kis, A. J. Kulik, and L. Forró, "Elastic modulus of multi-walled carbon nanotubes produced by catalytic chemical vapour deposition ", Appl. Phys. A 80 , 695-700 (2005).
J. Dorsaz, J. F. Carlin, S. Gradečak, and M. Ilegems, "Progress in AlInN-GaN Bragg reflectors: Application to a microcavity light emitting diode ", J. Appl. Phys. 97 , 084505 (2005).
S. Gradečak, P. Stadelmann, V. Wagner, and M. Ilegems, "Bending of dislocations in GaN during epitaxial lateral overgrowth ", Appl. Phys. Lett. 85 , 4648-4650 (2004).
F. Qian, Y. Li, S. Gradečak, D. L. Wang, C. J. Barrelet, and C. M. Lieber, "Gallium nitride-based nanowire radial heterostructures for nanophotonics ", Nano Lett. 4 , 1975-1979 (2004).
D. C. Bell, Y. Wu, C. J. Barrelet, S. Gradečak, J. Xiang, B. P. Timko, and C. M. Lieber, "Imaging and analysis of nanowires ", Microsc. Res. Tech. 64 , 373-389 (2004).
J. Napierala, D. Martin, H. J. Buhlmann, S. Gradečak, and M. Ilegems, "GaN laterally overgrown on sapphire by low pressure hydride vapor phase epitaxy ", Mat. Sci. Forum, Part 2 457-460 , 1581-1584 (2004).
J. Dorsaz, J. F. Carlin, C. M. Zellweger, S. Gradečak, and M. Ilegems, "InGaN/GaN resonant-cavity LED including an AlInN/GaN Bragg mirror ", phys. status solidi (a) 201 , 2675-2678 (2004).
S. Gradečak, M. Albrecht, H. P. Strunk, D. Martin, J. Napierala, M. Ilegems, P. Stadelmann, "Microstructure and optical properties of ELO-GaN layers grown by hydride vapor phase epitaxy", Institute of Physics Conference Series 180 , 321-324 (2003).
S. Gradečak, V. Wagner, M. Ilegems, T. Riemann, J. Christen, and P. Stadelmann, "Microscopic evidence of point defect incorporation in laterally overgrown GaN ", Appl. Phys. Lett. 80 , 2866-2868 (2002).
J. C. Lasjaunias, M. Saint-Paul, A. Bilsic, A. Smontara, S. Gradečak, A. M. Tonejc, A. Tonejc, and N. Kitamura, "Acoustic and thermal transport properties of hard carbon formed from C60 fullerene ", Phys. Rev. B 66 , 014302 (2002).
V. Wagner, O. Parillaud, H. J. Buhlmann, M. Ilegems, S. Gradečak, and P. Stadelmann, "Influence of the carrier gas composition on morphology, dislocations and microscopic luminescence properties of selectively grown GaN by HVPE ", J. Appl. Phys. 92 , 1307-1316 (2002).
A. Smontara, A. M. Tonejc, S. Gradečak, A. Tonejc, A. Bilusic, and J. C. Lasjaunias, "Structural (XRD and HRTEM) investigations of fullerite C60 and C70 samples ", Mat. Sci. Eng. C 19 , 21-25 (2002).
G. Zgrablic, D. Vinkovic, S. Gradečak, D. Kovacic, N. Biliskov, N. Grbac, Z. Andreic, and S. Garaj, "Instrumental recording of electrophonic sounds from Leonid fireballs ", J. Geoph. Res. 107 , 1124 (2002).
A. Smontara, A. Bilusic, J. C. Lasjaunias, M. Saint-Paul, S. Gradečak, A. Mejski-Tonejc, A. Tonejc, N. Kitamura, and S. Bennington, "Thermal and elastic properties of hard carbon", Strojarstvo 44 , 195-200 (2002).
S. Gradečak, V. Wagner, M. Ilegems, F. Bobard, P. Stadelmann, “Microstructure of ELO-GaN Layers Grown by Hydride Vapour Phase Epitaxy ”, Res. Soc. Symp. Proc. 693 , I3.23 (2001), edited by J.E. Northrup, J. Neugebauer, S.F. Chichibu, D.C. Look and H. Riechert
A. Bilusic, S. Gradečak, A. Tonejc, A. T. Tonejc, J. C. Lasajunias, and A. Smontara, "Transport properties of fullerite samples ", Synthetic Metals 121 , 1121-1122 (2001).