All-reflective UV-VIS-NIR transmission and fluorescence spectrometer for μm-sized samples

Abstract

We report on an optical transmission spectrometer optimized for tiny samples. The setup is based on all-reflective parabolic optics and delivers broadband operation from 215 to 1030 nm. A fiber-coupled light source is used for illumination and a fiber-coupled miniature spectrometer for detection. The diameter of the probed area is less than 200 μm for all wavelengths. We demonstrate the capability to record transmission, absorption, reflection, fluorescence and refractive indices of tiny and ultrathin sample flakes with this versatile device. The performance is validated with a solid state wavelength standard and with dye solutions.

Coherent ultrafast lattice-directed reaction dynamics of triiodide anion photodissociation

“…The steady-state absorption spectra of solid-state TBAT were measured with a home-built microspectrometer 47 employing a fiber-coupled deuterium halogen lamp (Ocean Optics, DH-2000-BAL) with ~ 100 μm focus size at the sample position. The solution spectra were measured with quartz cuvettes in a commercial spectrophotometer (Shimadzu UV-2600).…”

Fixed target combined with spectral mapping: approaching 100% hit rates for serial crystallography

“…To increase the hit rate, we have developed a high-speed UV/Vis microspectrometer (adapted from Kirchner et al, 2014), with a focus spot size of 100 micron and covered wavelength range of 200 – 850 nm) to map crystal positions in the chip. Transmission spectra are recorded from each feature to determine whether or not it harbours a crystal.…”

“…A fiber-coupled microfocus absorption spectroscopy setup for sample characterization and chip mapping was developed (adapted from Kirchner et al, 2014). The setup utilizes a fiber-coupled broadband LED light source, off-axis parabolic mirrors, a fiber-coupled USB spectrometer, and a 3-axis translation stage (SmarAct) for accurate sample positioning (similar to the beamline end station described in Sherrell et al, 2015).…”

Sub-phonon-period compression of electron pulses for atomic diffraction

“…Diffraction is either produced by focusing the electron beam on the screen (highest coherence) or on the sample (highest yield) 57 . Fluorescence spectroscopy from the nm-thick layer 65 revealed the expected ultrafast proton transfer via a huge Stokes shift; however, efficient pump–probe diffraction would require sub-20-fs ultraviolet excitation pulses at 340 nm, which are currently not available.…”