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The competition and interplay of topology and disorder has been one of the most famous topics in the field of condensed matter physics. In addition to the intuitive tendency to bring the system into a topologically trivial and localized phase, it has been discovered that disorder can also induce nontrivial topology and transport. To reveal rich and diverse phase structures, mapping phase diagrams plays an important role in both theoretical and experimental sides. Quantum simulation provides a prospective way to study the target model, explore the phase diagram and reveal the underlying mechanism. Thanks to the unprecedented controllability, superconducting quantum simulators have been introduced to investigate complex many-body physics and bring thought experiments into reality. To our best knowledge, the effort to map a phase diagram with a rich structure is still lacking. Here we report a systematic experimental study of the topology-disorder phase diagram with 32 qubits on a programmable analog quantum simulator. We implement one-dimensional (1D) disordered dimerized tight-binding models over a wide parameter range and observe diverse phases, including the topological Anderson insulator (TAI) and the inverse Anderson localization (IAL). Our experiment manifests the efficiency, accuracy and flexibility of the superconducting-circuit device and paves the way to the demonstration and understanding of many-body phenomena with noisy intermediate-scale quantum simulators.

In many fields, such as aerospace and marine environmental monitoring, magnetic field measurement is an important link. In recent years, optical fiber magnetic field sensor has received much attention because of its advantages such as small size, electromagnetic immunity, resistance to erosion and capability of remote sensing. In that case, magnetic fluid as a kind of medium between photons and magnetic field is widely used in optical fiber magnetic field sensors. Moreover, in the process of magnetic field measurement, disturbance introduced by temperature fluctuation always happens and brings uncertainty to the sensor. Temperature is also an important parameter in production process and needs to be measured. Therefore, designing a high-sensitive optical fiber sensor for simultaneously measuring magnetic field and temperature is a valuable work. In this paper, we present a high-sensitive hollow core fiber (HCF) interferometer for simultaneously measuring magnetic field and temperature. A segment of HCF filled with alcohol is inserted into single mode fiber (SMF) with 50 m offset at two splicing joints to guide light into the wall of HCF. And then this SMF-HCF-SMF structure is packaged by a capillary tube with full magnetic fluid (MF) inside it. Since the modal field area is large enough, the silica wall can support a series of guiding modes among which modal interference occurs and the interference spectrum can be recorded by an optical spectrum analyzer. Besides thermo-optic effect and thermal expansion effect of silica itself, the RI variations caused by thermo-optic effect of alcohol and MF as well as the magneto-optic effect of MF can also cause the phase difference of the guiding modes to change, thereby rendering interference dips movable. Thus, the sensitivity of temperature or magnetic field is higher than those given in some other previous studies. In addition, it is calculated that the effective RI sensitivities of guiding modes for inside and outside liquid are different because of the peculiar non-circular symmetry structure of HCF. So there is a possibility to find two dips in interference spectrum, which are formed with different modes and have various sensitivities to the variations of temperature and magnetic field. Finally, a sensitivity matrix can be built to demodulate those two parameters simultaneously. Experimental results show that within 20-58℃, the temperature sensitivities are 112 pm/℃ and 468 pm/℃ for dip1 and dip 2 whose magnetic field sensitivities are 37 pm/Oe and 82 pm/Oe within 0-169 Oe, respectively. The proposed sensor possesses high sensitivity and good mechanical strength, and can effectively eliminate the cross disturbances between temperature and magnetic field.

In this study, the fluorescence analysis was used to reveal the interaction between berberine derivatives and plasmid DNA. The results showed that berberine (C0) and its 8-alkyl derivatives can enhance the fluorescent intensity of plasmid DNA. Compared with 8-dodecyl- (C12) and 8-hexadecyl- (C16) berberine, 8-alkylberberine with shorter alkyl group, such as 8-ethyl (C2), 8-butyl (C4), 8-hexyl (C6), and 8-octyl (C8) berberine derivatives showed higher fluorescence increasing effect. Among all compounds, C4 showed highest fluorescence increasing effect. All compounds tested obviously enhanced fluorescent intensity at the concentration of 6.25 × 10(-5) mol/L. These results suggested that berberine and its derivatives can be selectively inserted to the grooves running down the plasmid DNA helix, thus, lead to the increase of fluorescence intensity of the reaction system. Also, adding proper length of aliphatic chain to berberine could promote the interaction between DNA and berberine derivatives. The results of this study may lay some useful foundation for the development of berberine-based medicine agents.

The performance of matched-field localization with a horizontal line array (HLA) at different depths in shallow water is investigated by normal mode modeling and computer simulation. It is observed that the matched-field localization performance of a bottom-mounted HLA is better than that of a HLA at other depths in shallow water. The normal mode modeling is used to explain this result. According to the normal mode theory, the mode shape is a function of water depth. The absolute values of the modes at different depths are compared. It is shown that the number of modes whose absolute values close to zero is smaller at the bottom than at other depths. It means that the HLA deployed at the bottom can sample more modes，obtain more information of the source and achieve better localization performance.

Seabed acoustic parameters are very important to underwater acoustic field prediction in shallow water. The existing inversion methods generally uses a vertical line array to receive the signal and its platform is stationary, which can not be operated for a large area with high resolution. The methods for extracting seabed reflection losses based on three kinds of line arrays were studied. A fast inversion scheme for the seabed acoustic parameters was presented, which uses a towed tilted line array and three acoustic sources to cover a large scope of grazing angles. The error analysis was made for this method. The simulation results show that different arrays require different experimental configurations to cover the same scope of grazing angles. The vertical line array must operate with several acoustic sources and require a stationary platform of the array. The towed horizontal line array needs only one acoustic source but requires a large-aperture line array. The towed tilted line array combines the merits of the vertical line array and the horizontal line array, which can inverse the seabed acoustic parameters in a moving and high resolution way and requires only a line array of smaller aperture.