Sabín Carlos, White Angela, Hackermuller Lucia, Fuentes Ivette
School of Mathematical Sciences, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom.
Quantum Systems Unit, Okinawa Institute of Science and Technology Graduate University, Onna-son, Okinawa 904-0495, Japan.
Sci Rep. 2014 Sep 22;4:6436. doi: 10.1038/srep06436.
We introduce a primary thermometer which measures the temperature of a Bose-Einstein Condensate in the sub-nK regime. We show, using quantum Fisher information, that the precision of our technique improves the state-of-the-art in thermometry in the sub-nK regime. The temperature of the condensate is mapped onto the quantum phase of an atomic dot that interacts with the system for short times. We show that the highest precision is achieved when the phase is dynamical rather than geometric and when it is detected through Ramsey interferometry. Standard techniques to determine the temperature of a condensate involve an indirect estimation through mean particle velocities made after releasing the condensate. In contrast to these destructive measurements, our method involves a negligible disturbance of the system.
我们介绍了一种用于测量处于亚纳开尔文温度范围的玻色-爱因斯坦凝聚体温度的原温度计。我们利用量子费舍尔信息表明，我们技术的精度在亚纳开尔文温度范围的温度测量方面提升了当前的技术水平。凝聚体的温度被映射到与该系统短时间相互作用的原子点的量子相位上。我们表明，当相位是动态而非几何的，并且通过拉姆齐干涉测量法进行检测时，可实现最高精度。确定凝聚体温度的标准技术涉及在释放凝聚体后通过平均粒子速度进行间接估计。与这些破坏性测量不同，我们的方法对系统的干扰可忽略不计。
