Guatieri Francesco
Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II) Technische Universität München, Lichtenbergstraße 1, 85748, Garching, Germany.
Sci Rep. 2025 Feb 18;15(1):5934. doi: 10.1038/s41598-025-89630-9.
Imaging the features of a sample using Positron Annihilation Spectroscopy (PAS) is currently achieved by rastering, i.e. by scanning the sample surface with a sharply focused positron beam. However, a beam of arbitrary shape (sculpted beam) would allow the application of more versatile single-pixel imaging (SPI) techniques. I introduce the design of a microelectronic device employing a 2D array of Zener diodes as an active positron moderator, capable of sculpting positron beams with [Formula: see text] resolution. The re-emitted positrons are accelerated towards the sample through a miniaturized electrostatic lens system and reaching [Formula: see text] resolution. The fast switch-on ([Formula: see text]) and switch-off ([Formula: see text]) time of the device would enable state-of-the-art positron annihilation lifetime spectroscopy (PALS) and PAS imaging with high spatial and temporal resolution.
目前,使用正电子湮没光谱(PAS)对样品特征进行成像,是通过光栅扫描实现的,即通过用聚焦很窄的正电子束扫描样品表面来实现。然而,具有任意形状的束流(雕刻束)将允许应用更通用的单像素成像(SPI)技术。我介绍了一种微电子器件的设计,该器件采用齐纳二极管二维阵列作为有源正电子慢化器,能够以[公式:见原文]分辨率雕刻正电子束。重新发射的正电子通过一个小型化的静电透镜系统朝着样品加速,并达到[公式:见原文]分辨率。该器件快速的开启([公式:见原文])和关闭([公式:见原文])时间将能够实现具有高空间和时间分辨率的先进正电子湮没寿命光谱(PALS)和PAS成像。