The Multi-Function Probe or MFP is a universal sample holder for the PPMS that allows users to incorporate their own experiment into the system. For example, the MFP is often equipped with coax- or high-voltage cables. It is also suited as sample holder for ferromagnetic resonance spectroscopy. For optical experiments, the MFP can be equipped with one or two light guide fibers. All fibers are fixed and vacuum-tight and can be used from 370 K down to 2 K. Together with our spectroscopy colleagues, we have performed a fluorescence measurement on an auto-fluorescent sample using a double-fiber MFP. The aim was to prove differences in the spectrum at very low temperatures. As light source we used a fiber-coupled 150 W xenon lamp with a bandpass filter from 450-490 nm.
A combination of a Czerny-Turner spectrograph (Andor SR-193i) and an sCMOS-camera (Andor Zyla-4.2P-USB3-S) was used to detect the spectrum. The picture on the left shows the MFP with illuminated sample. The figure on the right shows the measured fluorescen-ce spectra at 300 K and 10 K, normalized for the same maximum intensity. The emission band is smaller at low temperatures, the band maximum does not show any wavelength shifts. We can offer a completely set-up MFP with fibers to PPMS users and will upgrade one or two optical fibers on existing MFPs. Do you have samples for optical analyses in the PPMS? Please contact us if you want us to realize a measurement for you!