As a key component of electron multiplier device, a microchannel plate (MCP) can be applied in many scientific fields. Pure aluminum oxide (Al2O3) as secondary electron emission (SEE) layer were deposited in the pores of MCP via atomic layer deposition (ALD) to overcome problems such as high dark current and low lifetime which often occur on traditional MCP. In this paper, we systematically investigate the morphology, element distribution, and structure of samples by scanning electron microscopy (SEM) and energy disperse spectroscopy (EDS), respectively. Output current of different thickness of Al2O3 was studied and an optimal thickness was found. Experimental tests show that the average gain of ALD-MCP was nearly five times better than that of traditional MCP, and the ALD-MCP showed better sensitivity and longer lifetime.

Solid-state photon-enhanced thermionic emission (PETE) solar energy converters are newly proposed devices that can directly convert solar energy into electrical power at high temperatures. An analytical model based on a one-dimensional steady-state equation is developed to analyze the temperature-dependent performance of the solid-state PETE converter. The treatment used to derive the reverse saturation current density ( $J_0$ ) and open-circuit voltage ( $V_{oc}$ ) of the solid-state PETE converter is similar to that used in photovoltaic cells. Thus, their performances at elevated temperatures can be compared. Analysis results show that $J_0$ of the solid-state PETE converter with a GaAs absorption layer is approximately three orders of magnitude lower, and the decrease rate of open-circuit voltage ( $-d{V}_{oc}/dT$ ) is smaller than that of a practical GaAs photovoltaic cell. The improved performance of the solid-state PETE converter at high temperatures is attributed to the simultaneous use of diffusion and ballistic transport to harvest photo-generated electrons. The results presented in this paper demonstrate that, besides using wide bandgap materials and increasing doping density, harvesting solar energy via PETE effect can effectively improve the performance of solar cells at elevated temperatures.

As Moore's Law approaches its physical and technological limits, optical switching has emerged as a promising route to overcome the speed bottlenecks of conventional electronics. Ultrafast optical switches, with response times reaching the attosecond scale, hold great potential for next-generation photonic computing and high-speed communication systems. This review summarizes recent progress in ultrafast optical switching, emphasizing advances in materials (e.g., photonic crystals and 2D Mxenes), device architectures (e.g., metasurfaces and waveguides), and switching mechanisms (e.g., nonlinear optical effects and plasmonics). Key performance metrics, including switching speed (picosecond to attosecond), energy efficiency, and contrast, are systematically compared. The review first outlines the primary performance parameters of optical switches, then delves into the underlying quantum dynamics principles and technical approaches enabling ultrafast control. Subsequently, various ultrafast optical switching schemes are categorized and analyzed according to structural characteristics. Through comparisons across multiple parameters, the current research landscape and recent groundbreaking achievements in the field, including attosecond-scale optical modulation and low-loss lithium niobate integrated devices, are highlighted. Finally, future perspectives are discussed from the viewpoints of opto-electro-magnetic synergistic control and heterogeneous integration compatibility. This work aims to provide a comprehensive overview of the field, offering theoretical foundations and technical insights to guide the development of photonic computing chips and advanced optoelectronic technologies.

Attosecond streaking provides an extremely high temporal resolution for characterizing light pulses and photoionization processes with attosecond (10⁻¹⁸ s) accuracy, which employs a laser as a streaking field to deflect electrons generated by photoionization. The current attosecond streaking requires a time delay scan between the attosecond pulses and streaking field with attosecond accuracy and a femtosecond range, which is difficult to realize real-time measurement. In this study, we theoretically propose a non-collinear attosecond streaking scheme without the time delay scan, enabling real-time and even the potential to perform single-shot attosecond pulse measurement. In the proposal, time-delay information is projected into longitudinal space, both horizontally and vertically, enabling attosecond pulse characterization with temporal-spatial coupling. From our calculation, down to 70 as pulses with pulse front and wavefront tilt are characterized with high accuracy. Our study not only provides a method toward real-time attosecond pulse measurement, but also an approach for attosecond pump-probe experiments without time delay scan.