Time-resolved luminescence Z-scan of CsI using power femtosecond laser pulses

Abstract

Time-resolved Z-scan technique gives the opportunity to obtain consistent data for dependence of the yield and decay kinetics from excitation density. The excitation by 4 th harmonics of femtosecond Ti:Sapphire laser (6.2 eV) allows to measure with wide dynamical range of excitation density (from 10 17 to 10 22 excitations per cubic centimeter) CsI luminescence. In the density range 10 18 -10 19 cm -3 the yield of 310 nm band (fast intrinsic luminescence) increases linearly with energy of the laser pulse, and yield of 430 nm band decreases inversely. In the same density range the subnanosecond decay of 310 nm band becomes slower and in microsecond kinetics of 430 nm band increases the contribution of nanosecond components.

Decay Kinetics of CeF3 under VUV and X-ray Synchrotron Radiation

“…This quenching mechanism is similar to the quenching observed at high excitation densities in other systems with excitonic luminescence, e.g., CdWO 4 [29]. Luminescence quenching in such systems was observed in luminescence z-scan experiments using harmonics of a femtosecond laser [28,[30][31][32] and is well-described by the following formula:…”

Aurore: A platform for ultrafast sciences

“…The insert gives the maximal density of excitations obtained at different lens positions. The calculations of the created excitations density at different lens positions can be found in reference 79 .…”

Excitation Density Effects in the Luminescence Yield and Kinetics of MAPbBr3 Single Crystals

“…In the assumption of constant laser pulse output J, it allows for changing the excitation density by 400 times. The relation between the lens position Z and excitation fluence at the beam axis I0 (in the maximum of Gaussian distribution) is given by the following equations [13]: The characterization of the crystal structure of MAPbBr 3 crystals was carried out by the X-ray powder diffraction method on a Rigaku Ultima IV diffractometer with Bragg-Brentano geometry, using CuKα radiation.…”

“…In the assumption of constant laser pulse output J, it allows for changing the excitation density by 400 times. The relation between the lens position Z and excitation fluence at the beam axis I 0 (in the maximum of Gaussian distribution) is given by the following equations [13]:…”

“…Examples of such materials are ZnO, undoped CsI, and CsPbCl 3 [13]. These crystals have a low luminescence yield when excited in the fundamental absorption region (below the threshold of photon multiplication); however, their scintillation yield is reasonable when excited by X-rays or ionizing particles.…”