Article
Optics
Friedemann Landmesser, Tobias Sixt, Katrin Dulitz, Lukas Bruder, Frank Stienkemeier
Summary: Femtosecond coherent multidimensional spectroscopy is demonstrated for an ultracold gas in this article. A setup for phase modulation spectroscopy is used to probe the 32S1/2-22P1/ 2,3/2 transition in an 800 mu K-cold sample of 7Li atoms confined in a magneto-optical trap. The observation of a double quantum coherence response, a signature of interparticle interactions, paves the way for detailed investigations of few and many-body effects in ultracold gases using this technique. The experiment combines a frequency resolution of 3 GHz with a potential time resolution of 200 fs, which allows for high-resolution studies of ultracold atoms and molecules both in the frequency and in the time domain.
Article
Physics, Multidisciplinary
C. A. Bracamontes, J. Maslek, J. Porto
Summary: We experimentally engineer a moatlike dispersion in a system of weakly interacting bosons. By periodically modulating the amplitude of a checkerboard optical lattice, we hybridize the two lowest isolated bands and observe a continuum of nearly degenerate minima that lie along a circle in reciprocal space. This moatlike dispersion has a direct effect on the trajectory of the center of mass position of the condensate, and the decay of the condensates is found to increase rapidly as the quasimomentum decreases below the minimum of the moat.
PHYSICAL REVIEW LETTERS
(2022)
Article
Optics
Guosheng Feng, Zhixing Qiao, Tao Yin, Jizhou Wu, Hui Zhang
Summary: We conducted a comprehensive study on the optimized loading of ultracold Cs atoms in a magnetic levitated crossed dipole trap. The effects of the dipole laser's opening time and power intensity on the loading efficiency were analyzed. Experimental measurements showed that the number of atoms can be significantly increased through the pre-loading process.
Article
Optics
Yucheng He, Jing-Xin Liu, F-Q Guo, L-L Yan, Ronghui Luo, Erjun Liang, S-L Su, M. Feng
Summary: The scheme proposed in this study combines Vitanov-style pulses and dressed-state-based shortcut to adiabaticity (STA) to achieve multiple-qubit quantum state transfer and quantum logic gate in Rydberg atoms. By using STA technology to reduce the population of Rydberg excited states, the scheme demonstrates robustness to spontaneous emission, while well-designed pulses help minimize control errors. The dressed-state method applied in the scheme allows for smoother quantum state transfer operations with high fidelity, and is faster than traditional shortcut to adiabaticity methods.
OPTICS COMMUNICATIONS
(2022)
Article
Instruments & Instrumentation
M. A. W. van Ninhuijs, K. A. Daamen, J. Beckers, O. J. Luiten
Summary: In this study, a resonant microwave cavity is presented as a new diagnostic tool for studying ultracold plasmas, utilizing the shift in resonance frequency to monitor the evolution of the plasma. By laser-cooling gas and creating an ultracold plasma inside the cavity, the diagnostic method is shown to be fast, sensitive, and non-destructive. The characterization of the cavity and the response time determination demonstrate the effectiveness of the cavity as a sensitive probe for studying ultracold plasmas.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2021)
Article
Multidisciplinary Sciences
Marcell Gall, Nicola Wurz, Jens Samland, Chun Fai Chan, Michael Koehl
Summary: Researchers have used high-resolution microscopy to explore quantum phases in two-dimensional fermionic systems in optical lattices. By implementing a bilayer Fermi-Hubbard model, they found that interlayer coupling controls the crossover between different electronic states, potentially advancing future studies on superconducting properties of Hubbard models.
Article
Optics
Dmitry Obydennov, Konstantin B. Yushkov, Vladimir Ya Molchanov
Summary: This study reports a novel optical scheme of an annular optical trap based on an acousto-optic tunable spatial filter. The design of the optical trap was proposed and validated, with experimental demonstrations showing controllable arrangements of floating particles into circular patterns, aggregation, and disaggregation. The dynamical adjustment of the trapping field potential diameter was achieved through programmable frequency-swept controlling of the acousto-optic filter.
Article
Quantum Science & Technology
M. Marchenay, J. Pedregosa-Gutierrez, M. Knoop, M. Houssin, C. Champenois
Summary: RF linear multipole traps are highly sensitive to mis-positioning of their electrodes, leading to symmetry breaking and additional local minima in the trapping potential. This study analytically describes the RF-potential of a realistic octupole trap and proposes an equation for compensating electrode deviations. Fine-tuning the amplitude of the RF voltage applied on each electrode can mitigate geometrical defects, and an analytical equation for the potential allows designing the set of RF-voltages required for this compensation.
QUANTUM SCIENCE AND TECHNOLOGY
(2021)
Article
Physics, Multidisciplinary
Yafen Cai, Shuai Shi, Yijia Zhou, Jianhao Yu, Yali Tian, Yitong Li, Kuan Zhang, Chenhao Du, Weibin Li, Lin Li
Summary: This study demonstrates a novel atom-based microwave field amplitude stabilizer using microwave-dressed Rydberg atoms, which features multi-band frequency tunability and large stabilization bandwidth. The stabilization bandwidth achieved is two orders of magnitude higher than previous methods and can potentially be further increased. This research paves the way for developing noise-resilient, miniaturized, sensitive, and broadband electric field control and applications.
FRONTIERS OF PHYSICS
(2023)
Article
Physics, Multidisciplinary
M. Weyland, S. S. Szigeti, R. A. B. Hobbs, P. Ruksasakchai, L. Sanchez, M. F. Andersen
Summary: This study investigates the photoassociation dynamics of exactly two laser-cooled Rb-85 atoms in an optical tweezer and reveals fundamentally different behavior compared to photoassociation in many-atom ensembles. The nonexponential decay observed in the two-atom experiment cannot be described by a single rate coefficient and is attributed to the system's pair correlation. By probing the transition from two-atom dynamics to many-atom dynamics in a three-atom system, the experiments reveal additional reaction dynamics accessible through the control of single atoms and suggest the measurement of pair correlations in few-atom systems through photoassociation.
PHYSICAL REVIEW LETTERS
(2021)
Article
Multidisciplinary Sciences
Huan Yang, Xin-Yao Wang, Zhen Su, Jin Cao, De-Chao Zhang, Jun Rui, Bo Zhao, Chun-Li Bai, Jian-Wei Pan
Summary: The formation of triatomic molecules in mixtures of ultracold atoms and diatomic molecules using Feshbach resonance remains challenging. However, evidence of triatomic molecule association near the Feshbach resonance has been reported, and the binding energy of the triatomic molecules has been estimated.
Article
Optics
Dmitry Obydennov, Konstantin B. Yushkov, Vladimir Ya. Molchanov
Summary: We developed a tunable system for shaping the spectral and spatial frequency of ultrashort laser pulses using acousto-optic filters. This system allows for the creation of arbitrary axially symmetric multi-wavelength field configurations and enables high-speed control. Experimental results demonstrate the independent generation of different colored intensity distributions from a single laser beam using this system.
Article
Physics, Multidisciplinary
A. Ciamei, S. Finelli, A. Trenkwalder, M. Inguscio, A. Simoni, M. Zaccanti
Summary: This study investigates ultracold collisions in a novel mixture of Li-6 and Cr-53 fermionic atoms and discovers more than 50 interspecies Feshbach resonances via loss spectroscopy. By constructing a full coupled-channel model, the scattering properties of Li-6-Cr-53 are unambiguously characterized and predictions are made for other isotopic pairs. The identified Feshbach resonances allow for controlled tuning of elastic s- and p-wave Li-6-Cr-53 interactions. This research highlights the suitability of lithium-chromium mixtures for the experimental exploration of highly correlated fermionic matter and the realization of ultracold polar molecules with dual electric and magnetic dipole moments.
PHYSICAL REVIEW LETTERS
(2022)
Article
Physics, Multidisciplinary
Hauke Biss, Lennart Sobirey, Niclas Luick, Markus Bohlen, Jami J. Kinnunen, Georg M. Bruun, Thomas Lompe, Henning Moritz
Summary: In this work, we measured the excitation spectrum of strongly interacting ultracold Fermi gases using Bragg spectroscopy. The study revealed the smooth transformation from a bosonic to a fermionic superfluid in the BEC-BCS crossover. The results are in excellent agreement with previous experiments and calculations, especially when particle-hole correlations are taken into account.
PHYSICAL REVIEW LETTERS
(2022)
Review
Quantum Science & Technology
Shangguo Zhu, Yun Long, Wei Gou, Mingbo Pu, Xiangang Luo
Summary: Arrays of individual atoms trapped in optical microtraps offer a versatile platform for quantum sciences and technologies. By utilizing tunnel-coupled optical microtraps, researchers can explore exotic quantum states, phases, and dynamics that are challenging to achieve in conventional optical lattices.
ADVANCED QUANTUM TECHNOLOGIES
(2023)
