Atomic-resolution cryo-STEM across continuously variable temperature

Abstract

Atomic-resolution cryogenic scanning transmission electron microscopy (cryo-STEM) has provided a path to probing the microscopic nature of select low-temperature phases in quantum materials. Expanding cryo-STEM techniques to broadly tunable temperatures will give access to the rich temperature-dependent phase diagrams of these materials. With existing cryo-holders, however, variations in sample temperature significantly disrupt the thermal equilibrium of the system, resulting in large-scale sample drift. The ability to tune temperature without negatively impacting the overall instrument stability is crucial, particularly for high-resolution experiments.Here, we test a new side-entry continuously variable temperature dual-tilt cryo-holder which integrates liquid nitrogen cooling with a 6-pin MEMS sample heater to overcome some of these experimental challenges. We measure consistently low drift rates of 0.3-0.4 Å/s and demonstrate atomic-resolution cryo-STEM imaging across a continuously variable temperature range from ∼100 K to well above room temperature. We conduct additional drift stability measurements across several commercial sample stages and discuss implications for further developments of ultra-stable, flexible cryo-stages.

Review: Deep Learning in Electron Microscopy

“…Noise that is not statistical is often minimized by hardware. For example, by using aberration correctors 136,[157][158][159] , choosing scan shapes and speeds that minimize distortions 138 , and using stable sample holders to reduce drift 160 . Beam damage can also be reduced by using minimal electron voltage and electron dose [161][162][163] , or dose-fractionation across multiple frames in multi-pass TEM [164][165][166] or STEM 167 .…”