Topological Atomic Spinwave Lattices by Dissipative Couplings

Recent experimental advance in creating dissipative couplings provides a new route for engineering exotic lattice systems and exploring topological dissipation. Using the spatial lattice of atomic spinwaves in a vacuum vapor cell, where purely dissipative couplings arise from diffusion of atoms, we experimentally realize a dissipative version of the Su-Schrieffer-Heeger (SSH) model. We construct the dissipation spectra of the topological or trivial lattices via electromagnetically-induced-transparency (EIT) spectroscopy. The topological dissipation spectrum is found to exhibit edge modes at dissipation rates within a dissipative gap, decoupled from the bulk. We also validate chiral symmetry of the dissipative SSH couplings. This work paves the way for realizing topology-enabled quantum correlations and non-Hermitian topological quantum optics via dissipative couplings.Comment: 5 pages, 4 figure

Detection of entangled states supported by reinforcement learning

Discrimination of entangled states is an important element of quantum enhanced metrology. This typically requires low-noise detection technology. Such a challenge can be circumvented by introducing nonlinear readout process. Traditionally, this is realized by reversing the very dynamics that generates the entangled state, which requires a full control over the system evolution. In this work, we present nonlinear readout of highly entangled states by employing reinforcement learning (RL) to manipulate the spin-mixing dynamics in a spin-1 atomic condensate. The RL found results in driving the system towards an unstable fixed point, whereby the (to be sensed) phase perturbation is amplified by the subsequent spin-mixing dynamics. Working with a condensate of 10900 {87}^Rb atoms, we achieve a metrological gain of 6.97 dB beyond the classical precision limit. Our work would open up new possibilities in unlocking the full potential of entanglement caused quantum enhancement in experiments

A Non-stochastic Optimization Algorithm for Neural-network Quantum States

Neural-network quantum states (NQS) employ artificial neural networks to encode many-body wave functions in second quantization through variational Monte Carlo (VMC). They have recently been applied to accurately describe electronic wave functions of molecules and have shown the challenges in efficiency comparing with traditional quantum chemistry methods. Here we introduce a general non-stochastic optimization algorithm for NQS in chemical systems, which deterministically generates a selected set of important configurations simultaneously with energy evaluation of NQS. This method bypasses the need for Markov-chain Monte Carlo within the VMC framework, thereby accelerating the entire optimization process. Furthermore, this newly-developed non-stochastic optimization algorithm for NQS offers comparable or superior accuracy compared to its stochastic counterpart and ensures more stable convergence. The application of this model to test molecules exhibiting strong electron correlations provides further insight into the performance of NQS in chemical systems and opens avenues for future enhancements.Comment: 30 pages, 7 figures, and 1 tabl

OR-005 Effects of HIITand MICT for 10 weeks on myocardial AMPK and PGC-1α in rats

Objective: The improvement of cardiorespiratory fitness (CRF) is known as an effective strategy for prevention cardiovascular risk. Myocardial aerobic oxidation which control by the signal way of adenosine monophosphate -activated protein kinase (AMPK)- peroxisome proliferators γ activated receptor coativator-1-α (PGC-1α)  is the key for CRF. Previous studies only discuss the effect of the Moderate-Intensity Continuous Training (MICT) and High Intensive Interval Training (HIIT) on the signal way of AMPK- PGC-1α in skeletal muscle but not in the myocardium. The aim of this study was to compare the effects of 10 weeks HIIT and MICT on the expression of AMPK and PGC-1α in the myocardium of wistar male rats. Methods: Wistar male rats (n=30) aged 6 weeks were randomly divided into HIIT or MICT or control (CON) group. The training groups ran on a treadmill 5 days/week for 10 weeks. HIIT group ran six times 3 minutes (0° slope) 90% of Vmax separated by 3 minutes 50% of Vmax and MICT group ran for 50min (0° slope) at 60–70% of maximal speed (Vmax). The expression of AMPK and PGC-1α were assessed by Western Blotting. Results: After 10 weeks training, HIIT and MICT both increased the AMPK and PGC-1α expression compared with the CON group. Compared with the MICT group, the expression of AMPK and PGC-1α were significantly higher than the HIIT group (p<0.05). AMPK in MICT group were significant increased 1.16 times, and in HIIT group were significant increased 1.28 times to CON (P<0.05). PGC-1α level of HIIT was significant increased to 1.32 times to CON and also significant increased to 1.15 times to Group M (P<0.05); PGC-1α level of MICT was significant increased to 1.15 times to CON. Conclusion：HIIT seems to improve myocardial AMPK and PGC-1α more efficiently than MICT in rats after 10 weeks training.&nbsp

Beating the classical precision limit with spin-1 Dicke state of more than 10000 atoms

Interferometry is a paradigm for most precision measurements. Using $N$ uncorrelated particles, the achievable precision for a two-mode (two-path) interferometer is bounded by the standard quantum limit (SQL), $1/\sqrt{N}$, due to the discrete (quanta) nature of individual measurements. Despite being a challenging benchmark, the two-mode SQL has been approached in a number of systems, including the LIGO and today's best atomic clocks. Employing multi-mode interferometry, the SQL becomes $1/[(M-1)\sqrt{N}]$ using M modes. Higher precision can also be achieved using entangled particles such that quantum noises from individual particles cancel out. In this work, we demonstrate an interferometric precision of $2.42^{+1.76}_{-1.29}\,$dB beyond the three-mode SQL, using balanced spin-1 (three-mode) Dicke states containing thousands of entangled atoms. The input quantum states are deterministically generated by controlled quantum phase transition and exhibit close to ideal quality. Our work shines light on the pursuit of quantum metrology beyond SQL.Comment: 11 pages, 6 figure