Titan Krios

TFS Titan Krios with RF Cavity and Cs Probe Corrector

This instrument is a prototype TFS Titan Krios, equipped with a Cold-FEG, DrX Titan Chopper RF Cavity, Cs probe corrector, Autoloader, Ceta and Falcon4i camera, Dectris ELA detector, and TVIPS USG scan generator.

It is dedicated to the development of methods to improve the performance of cryo-EM structure analysis of biological macromolecules.

DrX Works RF Cavity+-

The resonant frequency cavity implements an ultrafast beam blanker, which is used to generate an electron illumination consisting of individual electrons, one at a time, yet at GHz repetition rate. The goal is to test, if such illumination could indeed reduce the electron beam damage on the biological specimen, as several other groups have recently reported for materials sciences specimens.

Cs Probe Corrector+-

The corrector for spherical lens aberrations above the specimen is used to allow a wide range of electron illumination conditions of the biological specimen. For example, a highly convergent illumination with a perfectly coherent electron beam reaching the sample with a semi-opening angle of 20mrad or more can easily be generated. This is used to develop convergent beam electron diffractive imaging for biological samples, such as ptychography or other 4D STEM applications.

In this project, we collaborate with the laboratories of Prof. Knut Müller-Caspary (TU Münich, Germany), and Prof. Carsten Sachse (ER-C Jülich, Germany).

Look inside+-

The RF Cavity and the Cs probe corrector are non-standard features of this instrument.

Parameters of the instrument+-

Accelerating Voltage 80 ... 300 kV
Electron Source E-CFEG (Cold FEG)
Stage Tilt Range ± 70°
C1 Apertures 2000, 70, 50 and 30 µm
Stroboscopic single electron gun RF Cavity DrX.works Titan Chopper
C2 Apertures 150, 70, 50 and 20 µm
Aberration corrector Cs probe corrector S CORR with Auto S CORR software
Objective apertures 100, 70 and 30 µm
Selected area apertures 200, 100, 40 and 10 µm
Operating Temperature ~80 K
Information Limit at 300kV at 0° / ±70° tilt 0.12 nm / 0.23 nm
Cs 2.7 mm
Number of cartridge positions for grids 12 total
Sample exchange time ~3 mins from autoloader cassette to column
STEM detector Panther STEM detector with OptiSTEM software
Camera CETA 16M (300kV)
Camera Falcon4i
Falcon Camera pixels 14 micrometer pixel size, 4096x4096 pixels, Electron Event Recording capable
Falcon Camera Performance DQE (1/2 Nyquist) 0.72 (according to TFS)
Falcon Camera Performance DQE (Nyquist) 0.50 (according to TFS)
STEM scan generator TVIPS Universal Scan Generator (USG)
Hybrid pixel detector DECTRIS ELA detector (8500 frames per second)
Acquisition software SerialEM, EPU and TFS Tomography, home-built scan system. home-built online processing system