超流体约瑟夫森连接链中的非平衡运输:是否存在负差导电性?
Samuel E Begg1,2, Matthew J Davis2, Matthew T Reeves2
1Asia Pacific Center for Theoretical Physics, Pohang 37673, Korea.
Physical review letters
|March 22, 2024
概括
约瑟夫森连接链中的量子运输表明负差电导率 (NDC) 仅在弱合状态下有效. 量子波动显著影响填充动态,这表明与ac Josephson效应的混合行为.
科学领域:
- 量子物理学的量子物理学
- 凝聚物质物理学 凝聚物质物理学
- 原子物理 原子物理
背景情况:
- 在1D约瑟夫森连接链中远离平衡的量子运输动力学.
- 在多模式斯-爱因斯坦冷凝物中对负差电导率 (NDC) 的实验观测.
研究的目的:
- 开发一个理论模型来检查约瑟夫森连接链中NDC的实验结果.
- 研究量子波动和空间相变化对填充动态的作用.
- 澄清NDC解释的有效性,并探索混合行为.
主要方法:
- 量子运输动态的单元c场描述.
- 在各种道合中实验数据的定量复制.
- 分析量子波动导致的空间相位变化.
主要成果:
- 单元c场模型准确地复制了没有拟合参数的实验结果.
- 填充动态对来自量子波动的空间相变异非常敏感.
- 在弱合制度之外,NDC的解释无效.
结论:
- 该设备在弱合状态下表现出NDC和acJosephson效应的混合行为.
- 原子电子实现需要包含量子波动的模型.
- 在这个系统中,NDC的解释是有限的,并且取决于上下文.
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