標題: Ultralow 1/f Noise in a Heterostructure of Superconducting Epitaxial Cobalt Disilicide Thin Film on Silicon
作者: Chiu, Shao-Pin
Yeh, Sheng-Shiuan
Chiou, Chien-Jyun
Chou, Yi-Chia
Lin, Juhn-Jong
Tsuei, Chang-Chyi
電子物理學系
物理研究所
Department of Electrophysics
Institute of Physics
關鍵字: superconducting silicide/silicon heterostructure;interfacial dynamic defects;1/f resistance noise;dimer reconstruction;two-level-system fluctuators
公開日期: Jan-2017
摘要: High-precision resistance noise measurements indicate that the epitaxial CoSi2/Si heterostructures at 150 and 2 K (slightly above its superconducting transition temperature T-c of 1.54 K) exhibit an unusually low 1/f noise level in the frequency range of 0.008-0.2 Hz. This corresponds to an upper limit of Hooge constant gamma <= 3 X 10(-6), about 100 times lower than that of single-crystalline aluminum films on SiO2 capped Si substrates. Supported by high -resolution cross-sectional transmission electron microscopy studies, our analysis reveals that the 1/f noise is dominated by excess interfacial Si atoms and their dimer reconstruction induced fluctuators. Unbonded orbitals (i.e., dangling bonds) on excess Si atoms are intrinsically rare at the epitaxial CoSi2/Si(100) interface, giving limited trapping-detrapping centers for localized charges. With its excellent normal-state properties, CoSi2 has been used in silicon-based integrated circuits for decades. The intrinsically low noise properties discovered in this work could be utilized for developing quiet qubits and scalable superconducting circuits for future quantum computing.
URI: http://dx.doi.org/10.1021/acsnano.6b06553
http://hdl.handle.net/11536/133328
ISSN: 1936-0851
DOI: 10.1021/acsnano.6b06553
期刊: ACS NANO
Volume: 11
Issue: 1
起始頁: 516
結束頁: 525
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