An accurate measurement of the bunching of photons in the fluorescent emission from an ultracold ensemble of thermal 87Rb atoms in a steady-state magneto-optical trap is presented. Time-delayed-intensity-interferometry (TDII) performed with a 5-nanosecond time resolution yielded a second-order intensity correlation function that has the ideal value of 2 at zero delay, and that shows coherent Rabi oscillations of upto 5 full periods - much longer than the spontaneous emission lifetime of the excited state of Rb. The oscillations are damped out by ~150ns, and thereafter, as expected from a thermal source, an exponential decay is observed, enabling the determination of the temperature of the atomic ensemble. Values so obtained compare well with those determined by standard techniques. TDII thus enables a quantitative study of the coherent and incoherent dynamics, even of a large thermal ensemble of atomic emitters.
Bose-Einstein condensates (BECs) in free fall constitute a promising source for space-borne matter-wave interferometry. Indeed, BECs enjoy a slowly expanding wave function, display a large spatial coherence and can be engineered and probed by optical techniques. On a sounding rocket, we explore matter-wave fringes of multiple spinor components of a BEC released in free fall employing light-pulses to drive Bragg processes and induce phase imprinting. The prevailing microgravity played a crucial role in the observation of these interferences which not only reveal the spatial coherence of the con…
We present possible design concepts for a tractor atom interferometer (TAI) based on three-dimensional confinement and transport of ultracold atoms. The confinement reduces device size and wave-packet dispersion, enables arbitrary holding times, and facilitates control to create complex trajectories that allow for optimization to cancel unwanted sensitivity, fast splitting and recombination, and suppression of detrimental nonadiabatic excitation. Thus, the design allows for further advancement of compact, high-sensitivity, quantum sensing technology. In particular, we focus on the implementati…
Ultracold atoms in optical lattices are a powerful tool for quantum simulation, precise measurement, and quantum computation. A fundamental problem in applying this quantum system is how to manipulate the higher bands or orbitals in Bloch states effectively. Here we mainly review our methods for manipulating high orbital ultracold atoms in optical lattices with different configurations. Based on these methods, we construct the atom-orbital qubit under nonadiabatic holonomic quantum control and Ramsey interferometry with trapped motional quantum states. Then we review the observation of the nov…
Continuum-electron interferometry for enhancement of photoelectron circular dichroism and measurement of bound, free, and mixed contributions to chiral response
Progress towards quantum-enhanced interferometry with harmonically trapped quantum matter-wave bright solitons
本文研究了具有附加谐波囚禁的准一维波导中超冷玻色子原子的吸引相互作用动力学。首先，我们准备系统在其基态，然后移动零的谐波陷阱和开关附近的陷阱中心的额外的窄散射势。在与势垒碰撞两次后，我们建议测量与初始条件相反的原子数。量子增强干涉测量与量子亮孤子使我们能够预测检测的散射电位的偏移与单粒子实验相比，精度大大提高。在未来的实验实现中，这可能导致测量由重力势中的小水平梯度引起的弱力-分辨率为几微米，主要由孤子的大小决定。我们的数值模拟的基础上严格证明有效的潜在的方法[物理评论快报。102，010403（2009）和Phys. Rev. Lett. 103，210402（2009）]。我们选择我们的参数，使证明的先决条件（孤子不能分裂，能量的原因）总是满足，从而探索一个参数制度无法通过Gross-Pitaevskii方程的平均场描述由于薛定谔猫态发生在多粒子量子动力学。
Long-wavelength optical lattices from optical beatnotes: theory and applications
Istituto Nazionale di Ottica, Consiglio Nazionale delle Ricerche (CNR-INO)（意大利国家光学研究所，意大利国家研究委员会）；University of Naples “Federico II”（那不勒斯费德里科二世大学）；European Laboratory for Nonlinear Spectroscopy (LENS)（欧洲非线性光谱学实验室）；Institute of Nanotechnology, Consiglio Nazionale delle Ricerche (CNR-Nanotec)（意大利国家纳米技术研究所，意大利国家研究委员会）；Dipartimento di Fisica e Astronomia, Università di Bologna（博洛尼亚大学物理与天文学系）；University of Florence, Physics Department（佛罗伦萨大学物理系）；Department of Physics, University of the Basque Country UPV/EHU（巴斯克地区大学物理系）；IKERBASQUE, Basque Foundation for Science（伊克尔巴斯基奎，巴斯克科学基金会）
Ultra-cold atoms provide ideal platforms for interferometry. The macroscopic matter-wave property of ultra-cold atoms leads to large coherent length and long coherent time, which enable high accuracy and sensitivity to measurement. Here, we review our efforts to improve the performance of the interferometer. We demonstrate a shortcut method for manipulating ultra-cold atoms in an optical lattice. Compared with traditional ones, this shortcut method can reduce manipulation time by up to three orders of magnitude. We construct a matter-wave Ramsey interferometer for trapped motional quantum stat…
