Liquid Helium Cryogenic TEM below 1 {\AA}

Suk Hyun Sung; Maya Gates; Nishkarsh Agarwal; Yang Zhang; William Millsaps; Miti Shah; Emily Rennich; Cong Li; Pu Yu; Miaofang Chi; Benjamin H. Savitzky; Ismail El Baggari; Robert Hovden

arXiv · 2509.12475

Liquid Helium Cryogenic TEM below 1 {\AA}

Suk Hyun Sung·Maya Gates·Nishkarsh Agarwal·Yang Zhang·William Millsaps·Miti Shah·Emily Rennich·Cong Li·Pu Yu·Miaofang Chi·Benjamin H. Savitzky·Ismail El Baggari·Robert Hovden

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Abstract

Next-generation cryogenic transmission electron microscopes (TEM) aim to achieve high-resolution imaging at ultracold sample temperatures (< 90 K) and over extended hold times. Lower temperatures enable atomic-scale characterization with improved beam and dose resilience for organic specimens and access to emergent electronic phases in quantum materials. Side-entry liquid helium cooling stages presently lack the mechanical and thermal stability required to support sub-Angstrom information transfer in modern TEM. Here we demonstrate sub-Angstrom atomic imaging TEM with a side-entry stage at specimen temperatures down to ~20K and with low stage drift and stable hold times.

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Suk Hyun Sung, Maya Gates, Nishkarsh Agarwal, Yang Zhang, William Millsaps, Miti Shah, Emily Rennich, Cong Li, Pu Yu, Miaofang Chi, Benjamin H. Savitzky, Ismail El Baggari, Robert Hovden. 2025-09-15. Liquid Helium Cryogenic TEM below 1 {\AA}. https://arxiv.org/abs/2509.12475

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