SoftiMAX Experimental Station
The SoftiMAX STXM end-station is currently offering STXM and Ptychography imaging techniques to general users. It is a room-temperature system that operates down to 1e-6 mbar, but can also be back-filled with helium up to ambient pressure.
The STXM mode uses the PMT detector, and is limited in resolution by the spot size of the illumination. At 300 eV, the smallest spot size is about 30 nm, between 700 eV and 1600 eV, the smallest spot size is about 22 nm, and above 1600 eV the smallest spot size is about 60 nm. STXM can provide absorption contrast. The energy resolution is better than 50 meV in the commissioned energy range.
Fungal hyphae and Iron, STXM energy scan at the Fe-L edge (M. Pucetaite et al.):
Carbon C-1s edge spectra from SoftiMax STXM (left), colour coded composite derived by fitting the stack to reference spectra (A. Hitchcock et al.):
XMCD imaging on a out-of-plane magnetized FeGd multilayer. Spectra measured with circular left and circular right X-rays, shown with difference (XMCD) spectrum and domain images for Iron Fe-L (left) and Gadolinium Gd-M edge (right). A. Hitchcock et al.:
The Ptychography mode uses a pixel detector; Currently the Andor Zyla is available. The sample can be moved out of focus to adjust the illumination spot size and the overlap. The detector distance can also be varied. The data can be analyzed on the MAX IV computing cluster using the Ptypy-package. Ptychography can provide both absorption and phase contrast.
Commissioning Ptychography image of an Au test pattern (phase contrast):
The following detectors are available:
|Detector type||Model and specification|
|Photodiode||Opto Diode Corp AXUV20HS1|
|PMT||Hamamatsu H3164-10, with P43 scintillator|
|2D detector||Andor Zyla 5.5, with FOP (3 μm channel diameter) and P43 scintillator (5 µm thickness); front-illuminated sCMOS, up to 100 fps; 2560 x 2160 pixels, 16.6 x 14.0 mm; The detector distance can be varied between 33 mm and about 150 mm.|
|2D detector||Tuscen Dhyana 95, direct detection; back-illuminated sCMOS, up to 24 fps; 2048 x 2048 pixels, 22.528 × 22.528 mm; 11 μm pixel size. Under commissioning|
|SDD||Amptek X123 Fast SDD,70mm2; C2 window (Si3N4). Under commissioning|