The preparation and optoelectronic response of flexible composites via noncovalent coupling of quantum dots to chemically converted graphene is presented. The photoinduced charge transfer is confirmed by photoconductivity measurements and the photosensitivity is improved with increasing loadings of quantum dots. This opens up a new effective route to form composites for future large‐area flexible and transparent optoelectronic devices.

A novel birefrmgent a-BaB2O4 crystal with 40mm in diameter, 35mm in height has been grown successfully in our laboratory by Czochralski method. The proportion of B203 and BaO of starting material, crystal cracking and the transmission spectrum of a-BaB2O4 crystal have been briefly analyzed.

The electrochemical mechanism of nanocrystalline silicon anode in sodium ion batteries is first studied via in operando Raman and in operando X‐ray diffraction. An irreversible structural conversion from crystalline silicon to amorphous silicon takes place during the initial cycles, leading to ultrafast reversible sodium insertion in the newly generated amorphous silicon. Furthermore, an optimized silicon/carbon composite has been developed to further improve its electrochemical performance.

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Sb3+ doping confers highly efficient and color-diverse broadband light emission to all-inorganic metal-halide perovskites. However, the emission mechanism is still under debate. Herein, a trace amount of Sb3+ ions (<0.1% atomic percentage) doping in the typical all-inorganic perovskites Cs2NaInCl6, Rb3InCl6, and Cs2InCl5·H2O allows universal observation of the fine structure in the photoluminescence excitation spectrum of the ns 2 electron. A lifetime mapping method was utilized to reveal the origin of broadband emission triggered by Sb3+ doping, by which various fluorescence components can be differentiated. In particular, free-exciton emission was identified at the high-energy end of the broadband emission for all three doped systems. The excitation-energy- and temperature-dependent fluorescence decay further indicates the existence and origin of self-trapped states. The observed structural and vibrational symmetry-dependent emission behaviors suggest dipole interactions can dramatically alter Stokes-shift energy and modulate the light-emitting wavelength.

Strong-field-enhanced spectroscopy in a hybrid dipole resonance system composed of a low-loss semiconductor nanoparticle and metal film is proposed and demonstrated. This hybrid Si nanoparticle on silver system is featuring extraordinary near-field enhancement and large field confinement. Extensive numerical calculations are carried out to investigate the influence of the gap size, particle diameter, and metal substrate on the near-field enhancement response in the Si particle–metal gap in order to properly model their hybridization. Our analysis reveals that this near-field enhancement originates from the strong gap magnetic resonance response by the Si nanoparticle dipole interaction with metal mirror image and metal film surface plasmon effects. We further demonstrate the strong enhanced Raman spectroscopy of a single silicon nanoparticle over Ag film with a precisely sized molecular spacer layer between them. These results illustrate the capacity and tunability of the low-loss silicon particle on the metal system on surface-enhanced spectroscopic techniques as well as possible applications in optical circuits or building new metamaterials.

Inorganic lead-free halide perovskites with a broadband emission of self-trapped excitons (STEs) have attracted great attention in lighting applications. However, it remains a fundamental challenge to expand the display color gamut because it is difficult to individually tune the emitting proportion at different wavelengths. Herein, we employ a doping route to incorporate Sb 3+ , Er 3+ , and Ho 3+ ions into the Cs 2 NaInCl 6 , which enables multicolor emissions with narrow full width at half-maxima and high photoluminescence quantum yields (PLQYs). The blue emission (445 nm) originates from STEs in the [SbCl 6 ] 3− octahedrons, while the narrowband green (550 nm) and red (655 nm) emissions are mainly derived from the Er 3+ and Ho 3+ ions, respectively. An efficient energy transfer between multiple luminescent centers is the key point to achieve such an efficient and tunable emission. By controlling the lanthanide doping level, the emission color can be systematically modulated, and cold 10401 K (0.278, 0.286) to warm 4608 K (0.347, 0.298) adjustable white-light emission (PLQY of ∼70%) can be achieved successfully. The results provide inspiration for the material design of lead-free perovskites with efficient and tunable light-emitting properties for optoelectronic applications.

We have investigated the propagation dynamics of super-Gaussian optical beams in fractional Schrödinger equation. We have identified the difference between the propagation dynamics of super-Gaussian beams and that of Gaussian beams. We show that, the linear propagation dynamics of the super-Gaussian beams with order m > 1 undergo an initial compression phase before they split into two sub-beams. The sub-beams with saddle shape separate each other and their interval increases linearly with propagation distance. In the nonlinear regime, the super-Gaussian beams evolve to become a single soliton, breathing soliton or soliton pair depending on the order of super-Gaussian beams, nonlinearity, as well as the Lévy index. In two dimensions, the linear evolution of super-Gaussian beams is similar to that for one dimension case, but the initial compression of the input super-Gaussian beams and the diffraction of the splitting beams are much stronger than that for one dimension case. While the nonlinear propagation of the super-Gaussian beams becomes much more unstable compared with that for the case of one dimension. Our results show the nonlinear effects can be tuned by varying the Lévy index in the fractional Schrödinger equation for a fixed input power.