在电路 QED 共振器中测量小光子数
Juan Atalaya1, Alex Opremcak1, Ani Nersisyan1
1Google Quantum AI, Santa Barbara, California 93111, USA.
Physical review letters
|June 3, 2024
概括
这项研究使用量子位移相测量低洞内光子数. 卡尔-普塞尔-梅布姆-吉尔技术准确地量化了共振器中的热和连贯光子群.
科学领域:
- 量子光学就是一个量子光学.
- 超导电路中的超导电路.
- 洞穴量子电动力学是什么意思
背景情况:
- 光子诱导的量子位变相是一种已知的现象.
- 在共振器中测量低光子数是具有挑战性的.
- 现有的方法对于小型光子群体缺乏精度.
研究的目的:
- 开发一种精确的方法来测量小平均数量的洞内光子.
- 量化连贯和热驱动的光子群体.
- 为了验证光子诱导脱相的理论模型.
主要方法:
- 利用波动光子和量子比特之间的非共振相互作用.
- 将卡尔-普尔塞尔-梅布姆-吉尔 (CPMG) 脉冲序列应用于量子位.
- 用非高斯噪声的衍生公式分析量子比特变相速率.
主要成果:
- 证明了热和连贯光子群的准确测量.
- 获得的灵敏度低至几 10^{-4} 平均光子.
- 在CPMG脱相率公式和实验数据之间显示出极好的一致性.
结论:
- 该CPMG技术是有效的测量低洞内光子数.
- 开发的脱相速公式准确地描述了实验观察结果.
- 这种方法为表征量子系统和共振器提供了一个新的工具.
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