UV-VIS TWO MODULATOR ELLIPSOMETER (2-MGE)

SYSTEM DESCRIPTION

The UV-VIS 2-MGE works in transmission and reflection modes with the PMSMA arrangement (manual goniometer). It simultaneously determines 9 of the 16 elements of the sample Mueller matrix with a single measurement and all of the 16 elements (complete Mueller matrix of the sample) with 4 measurements.

Spectral range: 260 to 750 nm (5,0 - 1,65 eV). The optical system is composed of:

• 75 W Xe short arc lamp,
• two calcite polarizer prisms (polarizer and analyzer),
• two photoelastic modulators oscillating at a frequencies of 50 kHz and 60 kHz respectively
• double grating monochromator
• photomultiplier tube

The data acquisition system is based on a two channel 12 bit high speed A/D PCI board with sample rate of 25 MS/s coupled to an I/O module. The typical acquisition time is around 8 ms for each experimental point. The I/O module controls the high voltage of the photomultiplier, the modulation amplitudes, the grating position of the monochromator and the rotation stages of the two modulators and the sample.

APPLICATIONS
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