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arXiv · 1711.00999

Thick Bi2Sr2CaCu2O8+δ films grown by liquid-phase epitaxy for Josephson THz applications

Y Simsek·V Vlasko-Vlasov·A E Koshelev·T Benseman·Y Hao·I Kesgin·H Claus·J Pearson·W-K Kwok·U Welp
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Abstract

Theoretical and experimental studies of intrinsic Josephson junctions that naturally occur in high-Tc superconducting Bi2Sr2CaCu2O8+δ (Bi-2212) have demonstrated their potential for novel types of compact devices for the generation and sensing of electromagnetic radiation in the THz range. Here, we show that the THz-on-a-chip concept may be realized in liquid phase epitaxial-grown (LPE) thick Bi-2212 films. We have grown μm-thick Bi-2212 LPE films on MgO substrates. These films display excellent c-axis alignment and single crystal grains of about 650x150 μm2 in size. A branched current-voltage characteristic was clearly observed in c-axis transport, which is a clear signature of underdamped intrinsic Josephson junctions, and a prerequisite for THz-generation. We discuss LPE growth conditions allowing improvement of the structural quality and superconducting properties of Bi-2212 films for THz applications.

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Y Simsek, V Vlasko-Vlasov, A E Koshelev, T Benseman, Y Hao, I Kesgin, H Claus, J Pearson, W-K Kwok, U Welp. 2017-11-03. Thick Bi2Sr2CaCu2O8+δ films grown by liquid-phase epitaxy for Josephson THz applications. https://doi.org/10.1088/1361-6668%2Faa987e

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