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Abstract The coexistence of gate-tunable superconducting, magnetic and topological orders in magic-angle twisted bilayer graphene provides opportunities for the creation of hybrid Josephson junctions. Here we report the fabrication of gate-defined symmetry-broken Josephson junctions in magic-angle twisted bilayer graphene, where the weak link is gate-tuned close to the correlated insulator state with a moiré filling factor of υ = −2. We observe a phase-shifted and asymmetric Fraunhofer pattern with a pronounced magnetic hysteresis. Our theoretical calculations of the junction weak link—with valley polarization and orbital magnetization—explain most of these unconventional features. The effects persist up to the critical temperature of 3.5 K, with magnetic hysteresis observed below 800 mK. We show how the combination of magnetization and its current-induced magnetization switching allows us to realise a programmable zero-field superconducting diode. Our results represent a major advance towards the creation of future superconducting quantum electronic devices.

The nanocarrier is linked to the core and shell by hydrogen bond. This drug delivery system represents a smart, biodegradable, and pH-sensitive nanocarrier for breast cancer therapy. These drug nanocarriers were linked by hydrogen bond from –NH2 on chitosan and –OH on mesoporous silica nanoparticle (MSN). And MSN was prepared by the cetyltrimethyl ammonium bromide (CTAB)-templated method via sol-gel and the loading of ibuprofen (IBU) into the pores of MSN was visualized by coprecipitation which was assessed by Fourier Transform Infrared Spectroscopy (FTIR) and nitrogen adsorption-desorption techniques. The wrapping of chitosan (CS) onto the surface of MSN was demonstrated by FTIR too. When the nanocarriers entered an acidic environment where large quantity cancer cells existed, the chitosan shell swell into loose random coil, exposing the drug and making them easy to be released. The results showed that the IBU could be successfully and effectively loaded into MSN and CS/MSN. The system was pH responsive. Drug release was much higher at pH 6.8 than at 7.4. This drug delivery system will represent a smart and biodegradable pH-responsive nanocarrier for breast cancer.

A compact circularly polarized (CP) patch antenna using a composite right/left-handed (CRLH) transmission line (TL) unit-cell is proposed. The CRLH TL unit-cell includes a complementary split ring resonator (CSRR) for shunt inductance and a gap loaded with a circular-shaped slot for series capacitance. The CSRR can decrease the TM10 mode resonance frequency, thus reducing the electrical size of the proposed antenna. In addition, the asymmetry of the CSRR brings about the TM01 mode, which can be combined with the TM10 mode by changing the slot radius. The combination of these two orthogonal modes with 90° phase shift makes the proposed antenna provide a CP property. The experimental results show that the proposed antenna has a wider axial ratio bandwidth and a smaller electrical size than the reported CP antennas. Moreover, the proposed antenna is designed without impedance transformer, 90° phase shift, dual feed and ground via.

The ICTP regional climate model (RegCM3) coupled with a desert dust aerosol model is used to simulate the net radiative forcing (short-wave and long-wave) and related climate effects of dust aerosols over East Asia. Two sets of experiments are completed and intercompared, one without (Exp. 1) and one with (Exp. 2) the radiative effects of dust aerosols. The experiments encompass the main dust producing months, February through May, for 10 years (1997–2006), and the simulation results are evaluated against ground station and satellite data. The model captures the basic observed climatology over the area of interest. The spatial and temporal variations of near surface concentration, mass load, optical depth and emission of dust aerosols from the main source regions are reproduced by model. The main model deficiency is an overestimate of dust amounts over the source regions and an underestimate downwind of these source areas, which indicates an underestimate of dust dispersal. Over the desert source regions, the net TOA radiative forcing is positive, while it is small over the other regions as a result of high surface albedo values which reduce the short-wave radiative forcing. The net surface radiative fluxes are decreased by dust and this causes a surface cooling locally up to −1°C. The inclusion of net (short-wave and long-wave) dust radiative forcing leads to a reduction of dust emission in the East Asia source regions, which is mainly caused by an increase in local stability and a corresponding decrease in dust lifting. Our results indicate that dust effects should be included in the assessment of climate change over East Asia.

A double-slot structure is proposed to design a new Vivaldi antenna with improved gain. The two slots are excited in uniform amplitude and phase by using a T-junction power divider. The double-slot structure can generate plane-like waves across the slot aperture of the antenna. As a result, the gain of the double-slot Vivaldi antenna is significantly improved compared with that of a typical Vivaldi antenna of the same size. The measured results show that the impedance bandwidth of the double-slot Vivaldi antenna is from 2.5 to 15 GHz. The gain of the proposed antenna is considerably higher than the typical antenna at frequencies above 6 GHz. What is more, the structure proposed is far simpler than those designed before. [ABSTRACT FROM AUTHOR]