Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 5 of 5
Full-Text Articles in Engineering
Dynamic Magneto-Optical Imaging Of Superconducting Thin Films, Frederick Wells, Alexey V. Pan, Stephen Wilson, Igor Golovchanskiy, Sergey Fedoseev, Anatoly B. Rosenfeld
Dynamic Magneto-Optical Imaging Of Superconducting Thin Films, Frederick Wells, Alexey V. Pan, Stephen Wilson, Igor Golovchanskiy, Sergey Fedoseev, Anatoly B. Rosenfeld
Australian Institute for Innovative Materials - Papers
We present a novel method for analysis of superconducting thin films using dynamic magneto-optical imaging, revealing hallmarks of flux penetration with temporal resolution around 1 ms (in the present work) or better. This method involves investigation of transient field and dynamic current distributions, which are calculated by an inversion procedure on the Biot-Savart Law, which we show to be valid under dynamic conditions. We compare and discuss the flux front penetration speed and evolution of current distribution in high quality YBa2Cu3O${}_{7-\delta }$ thin films with that of samples deliberately damaged in such a way as to reduce critical current density …
Tuning Superconductivity In Fese Thin Films Via Magnesium Doping, Wenbin Qiu, Zongqing Ma, Yongchang Liu, Md Shahriar Hossain, Xiaolin Wang, Chuanbing Cai, S X. Dou
Tuning Superconductivity In Fese Thin Films Via Magnesium Doping, Wenbin Qiu, Zongqing Ma, Yongchang Liu, Md Shahriar Hossain, Xiaolin Wang, Chuanbing Cai, S X. Dou
Australian Institute for Innovative Materials - Papers
In contrast to its bulk crystal, the FeSe thin film or layer exhibits better superconductivity performance, which recently attracted much interest in its fundamental research as well as in potential applications around the world. In the present work, tuning superconductivity in FeSe thin films was achieved by magnesium-doping technique. Tc is significantly enhanced from 10.7 K in pure FeSe films to 13.4 K in optimized Mg-doped ones, which is approximately 1.5 times higher than that of bulk crystals. This is the first time achieving the enhancement of superconducting transition temperature in FeSe thin films with practical thickness (120 nm) via …
Conductive And Protein Resistant Polypyrrole Films For Dexamethasone Delivery, Binbin Zhang, Paul J. Molino, Alexander R. Harris, Zhilian Yue, Simon E. Moulton, Gordon G. Wallace
Conductive And Protein Resistant Polypyrrole Films For Dexamethasone Delivery, Binbin Zhang, Paul J. Molino, Alexander R. Harris, Zhilian Yue, Simon E. Moulton, Gordon G. Wallace
Australian Institute for Innovative Materials - Papers
The development of inherently conducting polymers as controllable/programmable drug delivery systems has attracted significant interest in medical bionics, and the interfacial properties of the polymers, in particular, protein adsorption characteristics, is integral to the stability of the overall performance. Herein we report a hybrid conducting system based on polypyrrole doped with an anti-inflammatory prodrug, dexamethasone phosphate (DexP), upon which post-surface modification was conducted to render the polymer more biostable. We firstly investigated the influence of the current density and DexP concentration on the physiochemical properties and surface characteristics of the resulting polymer films. Films were then surface modified with thiolated …
Metal Frame As Local Protection Of Superconducting Films From Thermomagnetic Avalanches, Pavlo Mikheenko, J I. Vestgarden, Supratim Chaudhuri, I J. Maasilta, Y Galperin, Tom H. Johansen
Metal Frame As Local Protection Of Superconducting Films From Thermomagnetic Avalanches, Pavlo Mikheenko, J I. Vestgarden, Supratim Chaudhuri, I J. Maasilta, Y Galperin, Tom H. Johansen
Australian Institute for Innovative Materials - Papers
Thermomagnetic avalanches in superconducting films propagating extremely fast while forming unpredictable patterns, represent a serious threat for the performance of devices based on such materials. It is shown here that a normal-metal frame surrounding a selected region inside the film area can provide efficient protection from the avalanches during their propagation stage. Protective behavior is confirmed by magneto-optical imaging experiments on NbN films equipped with Cu and Al frames, and also by performing numerical simulations. Experimentally, it is found that while conventional flux creep is not affected by the frames, the dendritic avalanches are partially or fully screened by them. …
Interface-Enhanced Electron-Phonon Coupling And High-Temperature Superconductivity In Potassium-Coated Ultrathin Fese Films On Srtio3, Chenjia Tang, Chong Liu, Guanyu Zhou, Fangsen Li, Hao Ding, Zhi Li, Ding Zhang, Zheng Li, Canli Song, Shuaihua Ji, Ke He, Lili Wang, Xucan Ma, Qi-Kun Xue
Interface-Enhanced Electron-Phonon Coupling And High-Temperature Superconductivity In Potassium-Coated Ultrathin Fese Films On Srtio3, Chenjia Tang, Chong Liu, Guanyu Zhou, Fangsen Li, Hao Ding, Zhi Li, Ding Zhang, Zheng Li, Canli Song, Shuaihua Ji, Ke He, Lili Wang, Xucan Ma, Qi-Kun Xue
Australian Institute for Innovative Materials - Papers
Alkali-metal (potassium) adsorption on FeSe thin films with thickness from 2 unit cells (UC) to 4 UC on SrTiO3 grown by molecular beam epitaxy is investigated with a low-temperature scanning tunneling microscope. At appropriate potassium coverage (0.20-0.25 monolayer), the tunneling spectra of the films all exhibit a superconductinglike gap which is overall larger than 11 meV (five times the gap value of bulk FeSe) and decreases with increasing thickness, and two distinct features of characteristic phonon modes at ∼11 and ∼21 meV. The results reveal the critical role of the interface-enhanced electron-phonon coupling for possible high-temperature superconductivity in ultrathin FeSe …