论文标题
波动增强的量子计量学
Fluctuation-enhanced quantum metrology
论文作者
论文摘要
实用量子技术的主要障碍是噪声，它可以诱导折叠并破坏潜在的量子优势。诱导系统脱落的场的波动是最常见的噪声之一，被广泛认为是对量子技术有害的。在这里，我们表明，与常规信念相反，波动可用于提高量子计量学的精确限制以估计各种参数。具体而言，我们表明，为了估计场的方向和旋转频率，在波动的存在下达到的精确度甚至可以超过在统一动力学下可实现的最高精度，这已被广泛认为是最终的极限。我们提供采用自适应量子误差校正的显式协议，以实现更高的精度限制，并使用波动的字段。我们的研究为噪声在量子计量学中的作用提供了全新的观点。它还为更高的精确度打开了超出据信是最终的极限的更高精确度。
The main obstacle for practical quantum technology is the noise, which can induce the decoherence and destroy the potential quantum advantages. The fluctuation of a field, which induces the dephasing of the system, is one of the most common noises and widely regarded as detrimental to quantum technologies. Here we show, contrary to the conventional belief, the fluctuation can be used to improve the precision limits in quantum metrology for the estimation of various parameters. Specifically, we show that for the estimation of the direction and rotating frequency of a field, the achieved precisions at the presence of the fluctuation can even surpass the highest precision achievable under the unitary dynamics which have been widely taken as the ultimate limit. We provide explicit protocols, which employs the adaptive quantum error correction, to achieve the higher precision limits with the fluctuating fields. Our study provides a completely new perspective on the role of the noises in quantum metrology. It also opens the door for higher precisions beyond the limit that has been believed to be ultimate.
