N‐Type Superconductivity in an Organic Mott Insulator Induced by Light‐Driven Electron‐Doping. Issue 33 (29th June 2017)

• Record Type: Journal Article
• Authors: Suda, Masayuki; Takashina, Naoto; Namuangruk, Supawadee; Kungwan, Nawee; Sakurai, Hidehiro; Yamamoto, Hiroshi M.
• Is Part Of: Advanced materials. Volume 29:Issue 33(2017)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-06-29
• Subjects: field‐effect transistors -- Mott insulators -- photochromism -- superconductivity; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.201606833
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract : The presence of interface dipoles in self‐assembled monolayers (SAMs) gives rise to electric‐field effects at the device interfaces. SAMs of spiropyran derivatives can be used as photoactive interface dipole layer in field‐effect transistors because the photochromism of spiropyrans involves a large dipole moment switching. Recently, light‐induced p‐type superconductivity in an organic Mott insulator, κ‐(BEDT‐TTF)2 Cu[N(CN)2 ]Br (κ‐Br: BEDT‐TTF = bis(ethylenedithio)tetrathiafulvalene) has been realized, thanks to the hole carriers induced by significant interface dipole variation in the spiropyran‐SAM. This report explores the converse situation by designing a new type of spiropyran monolayer in which light‐induced electron‐doping into κ‐Br and accompanying n‐type superconducting transition have been observed. These results open new possibilities for novel electronics utilizing a photoactive SAMs, which can design not only the magnitude but also the direction of photoinduced electric‐fields at the device interfaces. Abstract : Light‐induced superconductivity in an organic Mott insulator is realized by light‐driven electron doping. This effect can be attributed to photoinduced built‐in potential formation in a photochromic‐spiropyran monolayer. The polarity of the photoinduced mobile carriers can be systematically controlled by designing the dipole moment variation of the spiropyran monolayers.