GHz sample excitation at the ALBA-PEEM

Muhammad Waqas Khaliq; José M. Álvarez; Antonio Camps; Nahikari González; José Ferrer; Ana Martinez-Carboneres; Jordi Prat; Sandra Ruiz-Gómez; Miguel Angel Niño; Ferran Macià; Lucia Aballe; Michael Foerster

doi:10.1016/j.ultramic.2023.113757

arXiv · 2305.06866

GHz sample excitation at the ALBA-PEEM

Muhammad Waqas Khaliq·José M. Álvarez·Antonio Camps·Nahikari González·José Ferrer·Ana Martinez-Carboneres·Jordi Prat·Sandra Ruiz-Gómez·Miguel Angel Niño·Ferran Macià·Lucia Aballe·Michael Foerster

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Abstract

We describe a setup that is used for high-frequency electrical sample excitation in a cathode lens electron microscope with the sample stage at high voltage as used in many synchrotron light sources. Electrical signals are transmitted by dedicated high-frequency components to the printed circuit board supporting the sample. Sub-miniature push-on connectors (SMP) are used to realize the connection in the ultra-high vacuum chamber, bypassing the standard feedthrough. A bandwidth up to 4 GHz with -6 dB attenuation was measured at the sample position, which allows to apply sub-nanosecond pulses. We describe different electronic sample excitation schemes and demonstrate a spatial resolution of 56 nm employing the new setup.

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Muhammad Waqas Khaliq, José M. Álvarez, Antonio Camps, Nahikari González, José Ferrer, Ana Martinez-Carboneres, Jordi Prat, Sandra Ruiz-Gómez, Miguel Angel Niño, Ferran Macià, Lucia Aballe, Michael Foerster. 2023-05-11. GHz sample excitation at the ALBA-PEEM. https://doi.org/10.1016/j.ultramic.2023.113757

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