Quantitative Determination of the Band Gap of WS<sub>2</sub> with Ambipolar Ionic Liquid-Gated Transistors

Article Article scientifique Article Quantitative Determination of the Band Gap of WS<sub>2</sub> with Ambipolar Ionic Liquid-Gated Transistors eng 2012 author Braga Danièle 745207 author Gutierrez Lezama Ignacio 681297 author Berger Helmuth author Morpurgo Alberto 666794 5218-5223 10.1021/nl302389d 1530-6984 We realized ambipolar field-effect transistors bycoupling exfoliated thin flakes of tungsten disulfide (WS2) with an ionic liquid dielectric. The devices show ideal electrical characteristics, including very steep subthreshold slopes for both electrons and holes and extremely low OFF-state currents. Thanks to these ideal characteristics, we determine with high precision the size of the band gap of WS2 directly from the gate-voltage dependence of the sourcedrain current. Our results demonstrate how a careful use of ionic liquid dielectrics offers a powerful strategy to study quantitatively the electronic properties of nanoscale materials Ionic liquid-gated transistors Ambipolar FETs Transition metal dichalcogenides Exfoliated crystals Dewey 500.2 33 Département de physique de la matière quantique 131 35 Groupe de physique appliquée 135 false 678 Groupe Morpurgo Nano letters 12 10 a8e6dac8-7c00-4358-a5b0-753b34c86839 Article (Published version) Restricted Morpurgo11.pdf 1842558 application/pdf restrictedAccess Faculté des sciences / Section de physique / Département de physique de la matière quantique Faculté des sciences / Section de physique / Groupe de physique appliquée

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Quantitative Determination of the Band Gap of WS₂ with Ambipolar Ionic Liquid-Gated Transistors	Nano letters			2012	632	1

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Braga, Danièle