DESCRIPTION

MIRAS is devoted to Fourier Transform Infrared (FTIR) spectroscopy and microscopy. FTIR is a very potential tool to identify the vibrational signatures and therefore the chemical composition of materials.

The beamline provide ALBA users with a modern synchrotron-based infrared spectrometer and microscope capability covering a wavelength range from about 1 µm to ∼100 µm with a spectral region optimized initially for investigation between 2.5-14 µm.

Transmission, Reflection, Attenuated total reflection (ATR) and Grazing incidence are the most important geometries for sample analysis, and are all available at the beamline.

IM-MIRAS_ExperimentalHutch  IM-MIRAS-OutsideTunnel  


STATUS

The beamline is now under commissioning. It will go into operation for users in autumn 2016

 

TECHNICAL SPECIFICATIONS 

Source Bending magnet - Full emission from the two main sources of radiation, edge and constant field of the bending magnet with opening angle of 43 mrad horizontal and 25.17 mrad vertical.
Energy range ~ 1.2 µm to 100 µm
Energy resolution 0.2 cm-1, (0.012meV) and higher ( up to 16 cm-1)
Flux on sample Approx. 4 e+13 Ph/s/0.1%bw@ 10 µm for 250 mA stored current or 8x10-7 W/cm-1
Beam size at sample position (full beam)    ~ 10x10 µm2 with a x36 objective
Projected Aperture size From 3x3µm2 and higher
Polarization properties Quasi-linear polarization from constant field emission of bending magnet, combined with radial polarization from edge radiation emission.

 

DETECTORS

The available detectors in the beamline are:

 

LAYOUT

BEAMLINE LAYOUT

The synchrotron radiation emitted in the infrared range from a bending magnet of the Storage Ring of ALBA was extracted from a modified dipole chamber, allowing acceptance-opening angle of 43(H) x 25.17(V) mrad2. The infrared beam is extracted in the horizontal plane using a laterally inserted flat mirror. MIRAS exploits the infrared synchrotron emission from the two main sources of radiation, edge and constant field emissions of the bending magnet. The optical layout of MIRAS includes the option for splitting the extracted infrared beam in two sectors, with one containing the edge radiation of the beam. This configuration will enable, in a future upgrade, the use of the two beams simultaneously at different endstations. The experimental cabin and transport optics are designed for such a future upgrade of the MIRAS beamline.

IM-MIRAS_OpticalLayout1               

Following the previously mentioned extraction geometry "horizontal then vertically upward deviation of the beam", a toroidal mirror M3 focusing the beam horizontally through the tunnel wall. After the first focus, the beam is made collimated using two cylindrical mirrors.

IM-MIRAS_OpticalLayout2