基于石墨烯的约瑟夫森交叉微波波计
Gil-Ho Lee1,2, Dmitri K Efetov3, Woochan Jung2
1Department of Physics, Harvard University, Cambridge, MA, USA.
Nature
|October 1, 2020
概括
我们开发了一种超薄的石墨烯测量仪, 这种新型传感器实现了热力学极限, 推动了广播天文学和量子科学应用.
科学领域:
- 物理
- 材料科学
- 量子技术
背景情况:
- 微波探测器对于无线电天文学,暗物质和量子信息科学至关重要.
- 传统的博洛米特在光子合和材料稳定性方面存在局限性,因为它们的表面与体积比较大.
- 较小设备的纳米制造是提高博洛米特灵敏度的典型方法.
研究的目的:
- 这是一个基于单层石墨烯的超薄玻利米传感器.
- 通过利用石墨烯独特的热和电子特性来克服传统的博洛米特的局限性.
- 在微波检测方面实现了前所未有的灵敏度.
主要方法:
- 开发了一种超导体-石墨烯-超导体约瑟夫森结合计.
- 在微波共振器中嵌入约瑟夫森连接器,共振频率为7.9GHz,合效率高于99%.
- 使用了石墨烯的低电子特异热和热导率.
主要成果:
- 达到 7 × 10−19 W/√Hz 的噪声等效功率.
- 显示了相当于一个32 GHz光子的能量分辨率.
- 在0.19K的温度波动下达到基本的灵敏度极限.
结论:
- 单层石墨烯可以开发超灵敏的玻利米传感器.
- 超导体 - 石墨烯 - 超导体约瑟夫森交叉波力计代表了探测器技术的重大进步.
- 在热力学极限创建波罗米特时,
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