Junjie Zhang

In this work, a series of Tm ³⁺ ‐doped TeO ₂ ‐BaO‐Nb ₂ O ₅ glasses were designed to elucidate the relationship between rare‐earth incorporation, thermal kinetic evolution, crystallization behavior, and near 2 μm emission properties. Differential scanning calorimetry (DSC) combined with kinetic analyses was employed to reveal the concentration‐dependent evolution of glass transition and crystallization kinetics. The apparent activation energies associated with glass transition (E _g ) and crystallization (E _c ) were evaluated using multiple kinetic models. With increasing Tm ₂ O ₃ concentration, the mean E _g increases from 567.25 to 1080.69 kJ/mol, whereas the mean E _c initially increases from 279.09 to 328.85 kJ/mol and subsequently decreases to 204.99 kJ/mol, indicating concentration‐dependent changes in thermal relaxation and crystallization processes. Avrami analysis provided insight into the possible crystallization behavior under the adopted kinetic models and non‐isothermal DSC conditions. XRD of heat‐treated samples supports this mechanism, showing one weak peak indicative of incipient surface crystallization nucleation, as predicted by kinetics. Optical measurements reveal that the glass containing 1.25 mol% Tm ₂ O ₃ exhibits the strongest 1.8 μm emission and a relatively long fluorescence lifetime of 1.635 ms. These findings provide insights into the design of thermally stable rare‐earth‐doped infrared luminescent glasses with tunable near‐2 μm emission.

The significant PL enhancement of the PQD glass is attributed to the energy transfer from Tb ³⁺ to CsPbBr ₃ . This mechanism is the result of the synergistic effect of FRET resonance energy transfer and non-radiative relaxation pathways.

Faced with the problem that the low modulation depth and saturation intensity of mid-infrared saturable absorbers (SAs) make it difficult to achieve higher pulse energy passively [ ]-switched, this paper successfully produced [ ]-switched and mode-locked mid-infrared 3[ ][ ]m lasers in fluoride fiber lasers using tellurium/graphene (Te/G) heterojunctions as SAs. Stable [ ]-switched pulses are achieved at low pump power, with a maximum repetition rate of 106.3[ ]kHz and a shortest pulse width of 2.36[ ][ ]s. The corresponding maximum output power reaches 63.1[ ]mW, with a slope efficiency of 25.5%, and the corresponding pulse energy is 0.594[ ][ ]J. Moreover, as the pump power increases, the laser enters the continuous-wave mode-locked state. The maximum average output power of the [ ]m mode-locked laser reaches 149.3[ ]mW at 1.19[ ]W, with a slope efficiency of 10.3%. This represents the first successful demonstration of passively [ ]-switched and mode-locked laser in fluoride lasers operating in the mid-infrared [ ]m region using Te/G heterojunction SA. The experimental results demonstrate that heterojunctions are an effective method to improve nonlinearity, which is a promising approach to achieve high-efficiency pulsed laser.

Currently, transition metal oxides (TMOs) are increasingly recognized as viable anode materials for lithium‐ion batteries (LIBs). Among them, V ₂ O ₅ has become a research focus in view of its high theoretical specific capacity, but its relatively low electrical conductivity and practical cycling capacity limit its application. It is shown that the amorphous V ₂ O ₅ ‐P ₂ O ₅ negative electrode material, due to its glassy structure, on the one hand, inhibits the volume strain and particle pulverization of graphite and vanadium components during charging and discharging processes and reduces the volume expansion phenomenon in battery cycling, and, on the other hand, the formation of ion‐conducting interfacial layer (PO ₄ ³ with Li⁺ ‐network) to promote lithium ion transport, which has a broad application prospect. Based on this, a series of (X) graphite‐(100‐X) vanadium‐pentoxide glass composite anode materials were prepared by mechanical ball milling method in this paper. The addition of graphite provides a stable layered structure and conductive network, realizes the reversible embedding/de‐embedding of lithium ions, improves the electrical conductivity of the composite materials, and reduces the charge transfer resistance of vanadium‐phosphorus glass anode materials in the cycling process. The performance of the five groups of composite anode materials showed an increasing and then decreasing trend, with the best performance observed in the 40% graphite‐60% vanadium‐based glass composites sample. Even after undergoing 500 cycles at 500 mA·g ⁻¹ , the material maintained high discharge and charge capacities of 509.3 and 510.2 mAh·g ⁻¹ , respectively, and the electrode sheet's surface remained relatively flat after cycling, with no obvious swelling, showing excellent cycling stability.

Perovskite quantum dots (PQDs) have shown great potential in lighting and display fields due to their excellent optical properties. However, their low red emission efficiency and poor environmental stability severely limit their practical applications. In this study, red-emitting Y₂O₃-modified CsPbBrI₂ PQD glass was prepared by high-temperature melt quenching and heat treatment methods with high luminescence and stability. The incorporation of Y³⁺ ions leads to a partial replacement of Pb²⁺ ions, resulting in a contraction of the crystal lattice. Y³⁺ ions will interact with the surface defects and halogen vacancies of PQDs to passivate these defect sites, thereby reducing the nonradiative recombination rate. The photoluminescent quantum yield increased from 5.6% to 56.4%, which is increased to ten times the original. The prepared CsPbBrI₂ PQD glass samples exhibited good thermal stability and water stability. Furthermore, red-emitting LED and WLED devices based on CsPbBrI₂ PQD glass achieved high color rendering index and good luminescent performance and stability. This paper presents Y₂O₃-modified CsPbBrI₂ PQD glass with efficient red-emitting emission and demonstrates its application potential in solid-state lighting and display technologies.

In this study, we demonstrate a high-performance passively mode-locked thulium-holmium (Tm-Ho) co-doped fiber laser utilizing a single-mode fiber–few-mode fiber–single-mode fiber (SMF-FMF-SMF) structure as an effective saturable absorber (SA) for noise-like pulse (NLP) generation. By solely adjusting the output coupling ratio from 30% to 50%, the maximum average output power at a pump power of 4.5 W is significantly increased from 238 mW to 391.2 mW in a single-pulse operation. The corresponding maximum pulse energy reaches 99.5 nJ at a repetition rate of 3.933 MHz, with a broad 3 dB bandwidth of 33.40 nm centered at 1948 nm. The laser exhibits excellent stability, as evidenced by a signal-to-noise ratio (SNR) of 69 dB. These results highlight the effectiveness of the SMF-FMF-SMF structure in improving output power and pulse characteristics, offering a promising approach for advancing high-energy mode-locked fiber lasers.

Phase-change-regulated dynamic time-dependent tunable persistent luminescence in α/β-Zn ₂ SiO ₄ :Mn ²⁺ embedded glass ceramics.

A novel PIGF system based on TeO ₂ glass@t-SiO ₂ for laser lighting was successfully synthesized. The laser damage threshold of 16 W mm ⁻² resulted in a maximum luminous flux of 1823 lm.