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Full-Text Articles in Condensed Matter Physics
Use Of Zwitterionic Molecules For Forming A Hole Or Electron Transport Layer, Bernard Doudin, Pierre Braunstein, Lucie Routaboul, Guillaume Dalmas, Zhengzheng Zhang, Peter Dowben
Use Of Zwitterionic Molecules For Forming A Hole Or Electron Transport Layer, Bernard Doudin, Pierre Braunstein, Lucie Routaboul, Guillaume Dalmas, Zhengzheng Zhang, Peter Dowben
Peter Dowben Publications
The invention relates to the use of zwitterionic molecules for forming a hole or electron transport layer. The preferred zwitterionic molecules of the invention are derivatives of p-benzoquinonemonoimines. The invention is useful in the field of electronic devices in particular.
Strain-Mediated Elastic Coupling In Magnetoelectric Nickel/Barium-Titanate Heterostructures, Robert Streubel, Denny Köhler, Rudolf Schäfer, Lukas M. Eng
Strain-Mediated Elastic Coupling In Magnetoelectric Nickel/Barium-Titanate Heterostructures, Robert Streubel, Denny Köhler, Rudolf Schäfer, Lukas M. Eng
Robert Streubel Papers
Multiferroic nanomaterials bear the potential for assembling a manifold of novel and smart devices. For room temperature (RT) applications, however, only the BiFeO3 single-phase perovskites are potential candidates to date. Nevertheless, vertical heterostructures separating magnetic and ferroelectric functionality into different layers are now widely proposed to circumvent this lack in materials' availability. We show here that the second approach is very profitable as illustrated by the strain-mediated coupling between such two layers, i.e., a ferroelectric barium titanate single-crystal (BTO) and a magnetostrictive nickel (Ni) thin film. Applying an electric field across the BTO substrate forces the magnetic easy axis in …
Adherent Cells Avoid Polarization Gradients On Periodically Poled Litao3 Ferroelectrics, Christof Christophis, Elisabetta Ada Cavalcanti-Adam, Maximilian Hanke, Kenji Kitamura, Alexei Gruverman, Michael Grunze, Peter A. Dowben, Axel Rosenhahn
Adherent Cells Avoid Polarization Gradients On Periodically Poled Litao3 Ferroelectrics, Christof Christophis, Elisabetta Ada Cavalcanti-Adam, Maximilian Hanke, Kenji Kitamura, Alexei Gruverman, Michael Grunze, Peter A. Dowben, Axel Rosenhahn
Peter Dowben Publications
The response of fibroblast cells to periodically poled LiTaO3 ferroelectric crystals has been studied. While fibroblast cells do not show morphological differences on the two polarization directions, they show a tendency to avoid the field gradients that occur between polarization domains of the ferroelectric. The response to the field gradients is fully established after one hour, a time at which fibroblasts form their first focal contacts. If suspension cells, with a lower tendency to establish strong surface contacts are used, no influence of the field gradients is observed.
Adsorption Of Tcnqh-Functionalized Quinonoid Zwitterions On Gold And Graphene: Evidence For Dominant Intermolecular Interactions+, Lingmei Kong, Lucie Routaboul, Pierre Braunstein, Hong-Gi Park, Jaewu Choi, John P. Colon Cordova, E Vega, Luis G. Rosa, Bernard Doudin, Peter A. Dowben
Adsorption Of Tcnqh-Functionalized Quinonoid Zwitterions On Gold And Graphene: Evidence For Dominant Intermolecular Interactions+, Lingmei Kong, Lucie Routaboul, Pierre Braunstein, Hong-Gi Park, Jaewu Choi, John P. Colon Cordova, E Vega, Luis G. Rosa, Bernard Doudin, Peter A. Dowben
Peter Dowben Publications
We experimentally investigate the electronic structure of the strongly dipolar, quinonoid-type molecule obtained by TCNQH-functionalization (TCNQH = (NC)2CC6H4CH(CN)2) of (6Z)-4-(butylamino)-6-(butyliminio)- 3-oxocyclohexa-1,4-dien-1-olate C6H2(...NHR)2(...O)2 (where R = n-C4H9) to be very similar after deposition from solution on either graphene or gold substrates. These zwitterion adsorbate thin films form structures that are distinct from those formed by related quinonoid molecules previously studied. We argue that adsorbate–adsorbate interactions dominate and lead to a Stranski–Krastanov ‘island growth’ mechanism.
Changing Molecular Band Offsets In Polymer Blends Of (P3ht/P(Vdf–Trfe)) Poly(3-Hexylthiophene) And Poly(Vinylidene Fluoride With Trifluoroethylene) Due To Ferroelectric Poling, Freddy Wong, Godohaldo Perez, Manuel Bonilla, Juan A. Colon-Santana, Xin Zhang, Pankaj Sharma, Alexei Gruverman, Peter A. Dowben, Luis G. Rosa
Changing Molecular Band Offsets In Polymer Blends Of (P3ht/P(Vdf–Trfe)) Poly(3-Hexylthiophene) And Poly(Vinylidene Fluoride With Trifluoroethylene) Due To Ferroelectric Poling, Freddy Wong, Godohaldo Perez, Manuel Bonilla, Juan A. Colon-Santana, Xin Zhang, Pankaj Sharma, Alexei Gruverman, Peter A. Dowben, Luis G. Rosa
Peter Dowben Publications
Photoelectron emission and inverse photoemission spectroscopy studies of polymer blends of poly(vinylidene fluoride (70%) – trifluoroethylene (30%)) P(VDF–TrFE 70 : 30) and regio-regular poly(3- hexylthiophene) (P3HT) provide evidence of changes in the molecular band offsets as a result of changes in the ferroelectric polarization in P(VDF–TrFE). Investigation of the blends with higher concentrations of the semiconducting P3HT component revealed that the organic semiconductor component of the blend dominates the electronic structure in the vicinity of the chemical potential. Specifically, the states of P3HT at the conduction band minimum and valence band maximum fall within the HOMO–LUMO gap of the dielectric …
Induced Magneto-Electric Coupling In Ferroelectric/Ferromagnetic Heterostructures, Jeffery Carvell, Ruihua Cheng, Peter A. Dowben, Q Yang
Induced Magneto-Electric Coupling In Ferroelectric/Ferromagnetic Heterostructures, Jeffery Carvell, Ruihua Cheng, Peter A. Dowben, Q Yang
Peter Dowben Publications
Using an external magnetic field, we have demonstrated room temperature control of the electric polarization of a ferroelectric polymer, polyvinylidene fluoride (PVDF), in an artificial multiferroic structure. For ferroelectric PVDF polymer thin films in an iron-PVDF-iron heterostructure, both the ferroelectric coercivity and polarization display a hysteresis dependence on the external magnetic field. We also find that the thickness of the PVDF layer has an effect on the magnetoelectric coupling in our samples. We observe a giant magnetoelectric coupling with values as large as 3700 V/cm Oe to 41700 V/cm Oe.
Magnetoelectric Coupling At The Euo/Batio3 Interface, Shi Cao, P Liu, Jinke Tang, Haidong Lu, C W. Bark, Sangjin Ryu, Chang-Beom Eom, Alexei Gruverman, Peter A. Dowben
Magnetoelectric Coupling At The Euo/Batio3 Interface, Shi Cao, P Liu, Jinke Tang, Haidong Lu, C W. Bark, Sangjin Ryu, Chang-Beom Eom, Alexei Gruverman, Peter A. Dowben
Peter Dowben Publications
Magnetization modulation by ferroelectric polarization switching is reported for the ferromagnetic-ferroelectric EuO/BaTiO3heterostructure. The value of the magnetization critical exponent β is consistent with the expected Heisenberg-like ferromagnetism of EuO and reported Curie temperature. The critical exponent is seen to decrease with increased magnetic coupling. The results are discussed in the context of data obtained earlier for epitaxial La0.67Sr0.33MnO3/BaTiO3 heterostructures, where magnetization increases and critical exponent b also declines with ferroelectric polarization pointing away from ferromagnetic layer. The observed similarity between two systems illustrates an importance of charge doping in magnetoelectric coupling, …