论文标题
纠缠增强的光原子钟
Entanglement-Enhanced Optical Atomic Clock
论文作者
论文摘要
最先进的原子钟基于对两个原子水平之间的能量差的精确检测，这些原子水平是在给定时间间隔中积累的量子相测量的。现在在与离散测量结果相关的量子噪声引起的标准量子限制（SQL）现在或接近标准量子限制（SQL）。尽管在微波钟和其他原子传感器中，通过工程量子相关性（纠缠）在原子之间实现了超出SQL的性能，但SQL超出SQL超出SQL的光锁转换和操作的纠缠产生代表了从未证明过的量子元学领域的主要目标。在这里，我们报告了在光学转变上创建多个原子状态的状态，并在SQL下方展示了具有Allan偏差的OLC。 We report a metrological gain of $4.4^{+0.6}_{-0.4}$ dB over the SQL using an ensemble consisting of a few hundred 171Yb atoms, allowing us to reach a given stability $2.8{\pm}0.3$ times faster than the same clock operated at the SQL.我们的结果应很容易适用于其他系统，从而在计时精度和准确性方面进一步进步。纠缠增强的OLC将具有许多科学和技术应用，包括对物理学，地理学或重力波检测的基本定律的精确测试。
State-of-the-art atomic clocks are based on the precise detection of the energy difference between two atomic levels, measured as a quantum phase accumulated in a given time interval. Optical-lattice clocks (OLCs) now operate at or near the standard quantum limit (SQL) that arises from the quantum noise associated with discrete measurement outcomes. While performance beyond the SQL has been achieved in microwave clocks and other atomic sensors by engineering quantum correlations (entanglement) between the atoms, the generation of entanglement on an optical-clock transition and operation of such a clock beyond the SQL represent major goals in quantum metrology that have never been demonstrated. Here we report creation of a many-atom entangled state on an optical transition, and demonstrate an OLC with an Allan deviation below the SQL. We report a metrological gain of $4.4^{+0.6}_{-0.4}$ dB over the SQL using an ensemble consisting of a few hundred 171Yb atoms, allowing us to reach a given stability $2.8{\pm}0.3$ times faster than the same clock operated at the SQL. Our results should be readily applicable to other systems, thus enabling further advances in timekeeping precision and accuracy. Entanglement-enhanced OLCs will have many scientific and technological applications, including precision tests of the fundamental laws of physics, geodesy, or gravitational wave detection.
