论文标题
在Bose-Einstein冷凝物中，温度接近绝对零的温度量子传感
Quantum sensing of temperature close to absolute zero in a Bose-Einstein condensate
论文作者
论文摘要
我们提出了一种理论方案，用于在准二维的玻色 - 因子凝结物（BEC）中对温度接近绝对零的量子传感。在我们的方案中，单原子杂质Qubit用作温度传感器。我们研究了单原子传感器在估计BEC温度时的灵敏度。我们证明，温度传感器的灵敏度可以通过测量探针量子量子的量子相干性的方式饱和量子cramer-rao。我们通过使用量子信噪比（QSNR）研究温度传感性能。据表明，有一个最佳的编码时间，QSNR可以在全温度方面达到其最大值。特别是，我们发现QSNR即使温度接近绝对零，QSNR即使在弱耦合方面达到有限的上限，这意味着在我们的方案中避免了传感误差问题。我们的工作为BEC中的绝对零接近绝对零的温度传感打开了一种方法。
We propose a theoretical scheme for quantum sensing of temperature close to absolute zero in a quasi-one-dimensional Bose-Einstein condensate (BEC). In our scheme, a single-atom impurity qubit is used as a temper-ature sensor. We investigate the sensitivity of the single-atom sensor in estimating the temperature of the BEC. We demonstrate that the sensitivity of the temperature sensor can saturate the quantum Cramer-Rao bound by means of measuring quantum coherence of the probe qubit. We study the temperature sensing performance by the use of quantum signal-to-noise ratio (QSNR). It is indicated that there is an optimal encoding time that the QSNR can reach its maximum in the full-temperature regime. In particular, we find that the QSNR reaches a finite upper bound in the weak coupling regime even when the temperature is close to absolute zero, which implies that the sensing-error-divergence problem is avoided in our scheme. Our work opens a way for quantum sensing of temperature close to absolute zero in the BEC.
