Thermostimulated luminescence measurments (TSL) is based on classical luminescence equipment consistion of 3 main parts: Excitation source (I), sample holder with cooler and heater (II) and spectrometer with detection unit (III).
(I) Different sources are available for sample excitation: X-ray source as well as different lasers (156nm, 193nm, 266nm, 337nm and 532nm).
(II) To cover temperature range from 10K to 800K three different heating systems are used:
*10-300K Closed cycle helium cryostat with heater
*80-600K Liquid nitrogen cryostats with heater
*300-800K Heaters, without active cooling
Sample chamber is connected to vacuum pump (pmin<10-2 torr) which allows to carry out measurements below room temperature
(III) Spectrometer consists from Andor Shamrock SR-303i spectrometer coupled with Andor iDus401 CCD.
Andor Shamrock SR-303ispectrometer: Czerny-Turner arrangement with imaging toroidal optics; focal length of 303mm, aperture f/4; wavelength resolution 0.1nm (<0.2nm with 25μm pixel CCD detector), wavelength reproducibility ± 0.05nm, wavelength accuracy ± 0.2nm. Gratings are mounted on interchangeable triple grating turret equipped with following gratings: 150 lines/mm, 600 lines/mm and 1200 lines/mm
Andor iDus401 (DU401A-BV) CCD: active pixels 1024×128, pixel size 26×26μm, Peltier element cooling up to -55°C, 81 spectra per second.
Besides spectrometer in detection part it is possible to use also photomultiplier tube with photon counting unit for low intensity TSL signal measurements.
Due to active heating and cooling systems this equipment is also used for FGT (fractional glow technique) allowing the direct measurement of trap excitation energies.
Besides this equipment, can be used as classical luminescence equipment, to measure luminescence temperature dependence etc.
Example of the measurements that can be performed on this setup:
Example A: alpha-quartz TSL measurement. 3D image can be obtained in a single measurement: spectral distribution is acquired at every temperature point.
Example B: Fraction Glow Technique (FGT) demostration in GAGG:Ce sample. Red line represents TSL signal from the sample and black dots are the trap activation energies with distinct steps observed at different energies corresponding to different TSL maxima.