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Jan Hendrik Schön - Wikipedia, the free encyclopedia

Jan Hendrik Schön

From Wikipedia, the free encyclopedia

Jan Hendrik Schön (born 1970) is a German physicist who briefly rose to prominence after a series of apparent breakthroughs that were later discovered to be fraudulent.[1] Before he was exposed, Schön had received the Otto-Klung-Weberbank Prize for Physics in 2001, the Braunschweig Prize in 2001 and the Outstanding Young Investigator Award of the Materials Research Society in 2002.

The Schön scandal provoked discussion in the scientific community about the degree of responsibility of coauthors and reviewers of scientific papers. The debate centered on whether peer review traditionally designed to find errors and determine relevance and originality of papers, should also be required to detect deliberate fraud.

Contents

[edit] Rise to prominence

Schön's field of research was condensed matter physics and nanotechnology. He received his Ph.D. from the University of Konstanz in 1997. In late 1997 he was hired by Bell Labs.

In 2001 he was listed as an author on an average of one research paper every eight days. In that year he announced in Nature that he had produced a transistor on the molecular scale. Schön claimed to have used a thin layer of organic dye molecules to assemble an electric circuit that, when acted on by an electric current, behaved as a transistor. The implications of his work were significant. It would have been the beginning of a move away from silicon-based electronics and towards organic electronics. It would have allowed chips to continue shrinking past the point at which silicon breaks down, and therefore continue Moore's Law for much longer than is currently predicted. It also would have drastically reduced the cost of electronics.

[edit] Allegation and investigation

Soon after he published his work, others in the physics community alleged that Schön's data contained anomalies. In particular they said the data seemed overly precise, and that some of it contradicted the prevailing understanding of physics. Professor Lydia Sohn, then of Princeton University, noticed that two experiments carried out at very different temperatures had identical noise. When the editors of Nature pointed this out to Schön, he claimed to have accidentally submitted the same graph twice. Professor Paul McEuen of Cornell University then found the same noise in a paper describing a third experiment. More research by McEuen, Sohn and other physicists, uncovered a number of examples of duplicate data in Schön's work. In total, 25 papers by Schön and 20 coauthors were considered suspect.

In May 2002 Bell Labs appointed Professor Malcolm Beasley of Stanford University to chair a committee to investigate possible scientific fraud. The committee sent questionnaires to all of Schön's coauthors and interviewed his three principal coauthors (Zhenan Bao, Bertram Batlogg and Christian Kloc). It examined electronic drafts of the disputed papers which included processed numeric data. The committee requested copies of the raw data but found that Schön had kept no laboratory notebooks. His raw-data files had been erased from his computer. According to Schön the files were erased because his computer had limited hard drive space. In addition, all of his experimental samples had been discarded, or damaged beyond repair.

On September 25, 2002, the committee publicly released its report. The report contained details of 24 allegations of misconduct. They found evidence of Schön's scientific misconduct in at least 16 of them. They found that whole data sets had been reused in a number of different experiments. They also found that some of his graphs, which purportedly had been plotted from experimental data, had instead been produced using mathematical functions.

The report found that all of the misdeeds had been performed by Schön alone. All the coauthors were completely exonerated of scientific misconduct. It was, however, unclear whether all of them had exercised sufficient professional responsibility in trusting the integrity of his data.[citation needed]

Bell Labs fired Schön on the day they received the report. It was the first known case of fraud in the Lab's history.

[edit] Withdrawn journal papers

On October 31, 2002, Science withdrew eight papers written by Schön:[2]

  • J. H. Schön, S. Berg, Ch. Kloc, B. Batlogg, Ambipolar pentacene field-effect transistors and inverters, Science 287, 1022 (2000)
  • J. H. Schön, Ch. Kloc, R. C. Haddon, B. Batlogg, A superconducting field-effect switch, Science 288, 656 (2000)
  • J. H. Schön, Ch. Kloc, B. Batlogg, Fractional quantum Hall effect in organic molecular semiconductors, Science 288, 2338 (2000)
  • J. H. Schön, Ch. Kloc, A. Dodabala-pur, B. Batlogg, An organic solid state injection laser, Science 289, 599 (2000)
  • J. H. Schön, A. Dodabalapur, Ch. Kloc, B. Batlogg, A light-emitting field-effect transistor, Science 290, 963 (2000)
  • J. H. Schön, Ch. Kloc, H. Y. Hwang, B. Batlogg, Josephson junctions with tunable weak links, Science 292, 252 (2001)
  • J. H. Schön, Ch. Kloc, B. Batlogg, High-temperature superconductivity in lattice-expanded C60, Science 293, 2432 (2001)
  • J. H. Schön, H. Meng, Z. Bao, Field-effect modulation of the conductance of single molecules, Science 294, 2138 (2001)

On December 20, 2002, the Physical Review journals withdrew six papers written by Schön:[citation needed]

  • J. H. Schön, Ch. Kloc, R. A. Laudise, and B. Batlogg, Electrical properties of single crystals of rigid rodlike conjugated molecules, Phys. Rev. B 58, 12952-12957 (1998)
  • J. H. Schön, Ch. Kloc, and B. Batlogg, Hole transport in pentacene single crystals, Phys. Rev. B 63, 245201 (2001)
  • J. H. Schön, Ch. Kloc, D. Fichou, and B. Batlogg, Conjugation length dependence of the charge transport in oligothiophene single crystals, Phys. Rev. B 64, 035209 (2001)
  • J. H. Schön, Ch. Kloc, and B. Batlogg, Mobile iodine dopants in organic semiconductors, Phys. Rev. B 61, 10803-10806
  • J. H. Schön, Ch. Kloc, and B. Batlogg, Low-temperature transport in high-mobility polycrystalline pentacene field-effect transistors, Phys. Rev. B 63, 125304 (2001)
  • J. H. Schön, Ch. Kloc, and B. Batlogg, Universal Crossover from Band to Hopping Conduction in Molecular Organic, Phys. Rev. Lett. 86, 3843-3846 (2001)

On March 5, 2003, Nature withdrew seven papers written by Schön:[3] [4] [5] [6] [7] [8] [9]

  • Schön, J. H., Kloc, Ch. & Batlogg, B. Superconductivity at 52K in hole-doped C60. Nature 408, 549-552 (2000).
  • Schön, J. H. et al. Gate-induced superconductivity in a solution-processed organic polymer film. Nature 410, 189- 192 (2001).
  • Schön, J. H., Meng, H. & Bao, Z. Self-assembled monolayer organic field-effect transistors. Nature 413, 713-716 (2001).
  • Schön, J. H. et al. Superconductivity in single crystals of the fullerene C70. Nature 413, 831-833 (2001).
  • Schön, J. H. et al. Superconductivity in CaCuO2 as a result of field-effect doping. Nature 414, 434-436 (2001).

[edit] Aftermath and sanctions

Schön acknowledged that the data were incorrect in many of these papers. He claims that the substitutions could have occurred by honest mistake. He admits to falsifying some data and states he did so to show more convincing evidence for behaviour that he observed. He continues to maintain that his experiments worked and that molecular-sized transistors are possible using the techniques he demonstrated.

Experimenters at Delft University of Technology and the Thomas J. Watson Research Center have since performed experiments similar to Schön's. They did not obtain similar results. Also, before the allegations became public, several research groups tried to reproduce most of the groundbreaking results in the field of the physics of organic molecular materials - without success.

In June 2004 the University of Konstanz tried to revoke Schön's doctoral degree due to "dishonorable conduct". Department of Physics spokesman Wolfgang Dieterich called the affair the "biggest fraud in physics in the last 50 years" and said that the "credibility of science had been brought into disrepute".[10] Schön appealed the decision, thus stopping the revocation process. As of July 2007, a final decision is still pending, and Schön still holds his doctoral degree.

In October 2004, the Deutsche Forschungsgemeinschaft (DFG) (trans.: German Research Foundation) Joint Committee announced sanctions against him. The former DFG post-doctorate fellow was deprived of his active right to vote in DFG elections or serve on DFG committees for an eight-year period. During that period, Schön will also be unable to serve as a peer reviewer or apply for DFG funds.[11]

[edit] See also

[edit] References

  1. ^ "Scandal Rocks Scientific Community", Deutsche Welle, 30 Sep 2002. 
  2. ^ Z. Bao, B. Batlogg, S. Berg, A. Dodabalapur, R. C. Haddon, H. Hwang, C. Kloc, H. Meng and J. H. Schon (2002). "Retraction". Science 298 (5595): 961b-. doi:10.1126/science.298.5595.961b. 
  3. ^ J. H. Schon, C. Kloc, E. Bucher and B. Batlogg (2003). "retraction: Efficient organic photovoltaic diodes based on doped pentacene". Nature 422 (6927): 93. doi:10.1038/nature01468. 
  4. ^ J. H. Schon, C. Kloc and B. Batlogg (2003). "retraction: Superconductivity in molecular crystals induced by charge injection". Nature 422 (6927): 93. doi:10.1038/nature01467. 
  5. ^ J. H. Schon, C. Kloc and B. Batlogg (2003). "retraction: Superconductivity at 52 K in hole-doped C60". Nature 422 (6927): 93. doi:10.1038/nature01466. 
  6. ^ J. H. Schon, A. Dodabalapur, Z. Bao, C. Kloc, O. Schenker and B. Batlogg (2003). "retraction: Gate-induced superconductivity in a solution-processed organic polymer film". Nature 422 (6927): 92. doi:10.1038/nature01465. 
  7. ^ J. H. Schon, H. Meng and Z. Bao (2003). "retraction: Self-assembled monolayer organic field-effect transistors". Nature 422 (6927): 92. doi:10.1038/nature01464. 
  8. ^ J. H. Schon, C. Kloc, T. Siegrist, M. Steigerwald, C. Svensson and B. Batlogg (2003). "retraction: Superconductivity in single crystals of the fullerene C70". Nature 422 (6927): 92. doi:10.1038/nature01463. 
  9. ^ J. H. Schon, M. Dorget, F. C. Beuran, X. Z. Zu, E. Arushanov, C. D. Cavellin and M. Lagues (2003). "retraction: Superconductivity in CaCuO2 as a result of field-effect doping". Nature 422 (6927): 92. doi:10.1038/nature01462. 
  10. ^ University of Konstanz (11 Jun 2004). "Universität Konstanz entzieht Jan Hendrik Schön den Doktortitel" (in German). Press release.
  11. ^ Deutsche Forschungsgemeinschaft. "DFG Imposes Sanctions Against Jan Hendrik Schön". Press release.

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