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arXiv · 1201.1558

Broadly Tunable Sub-terahertz Emission from Internal Branches of the Current-voltage Characteristics of Superconducting Bi2Sr2CaCu2O8+d Single Crystals

Manabu Tsujimoto·Takashi Yamamoto·Kaveh Delfanazari·Ryo Nakayama·Takeo Kitamura·Masashi Sawamura·Takanari Kashiwagi·Hidetoshi Minami·Masashi Tachiki·Kazuo Kadowaki·Richard A. Klemm
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Abstract

Continuous, coherent sub-terahertz radiation arises when a dc voltage is applied across a stack of the many intrinsic Josephson junctions in a Bi2Sr2CaCu2O8+d single crystal. The active junctions produce an equal number of I-V characteristic branches. Each branch radiates at a slightly tunable frequency obeying the ac Josephson relation. The overall output is broadly tunable and nearly independent of heating effects and internal cavity frequencies. Amplification by a surrounding external cavity to allow for the development of a useful high-power source is proposed.

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Manabu Tsujimoto, Takashi Yamamoto, Kaveh Delfanazari, Ryo Nakayama, Takeo Kitamura, Masashi Sawamura, Takanari Kashiwagi, Hidetoshi Minami, Masashi Tachiki, Kazuo Kadowaki, Richard A. Klemm. 2012-01-07. Broadly Tunable Sub-terahertz Emission from Internal Branches of the Current-voltage Characteristics of Superconducting Bi2Sr2CaCu2O8+d Single Crystals. https://doi.org/10.1103/physrevlett.108.107006

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