Multiwavelength thermal lens determination of fluorescence quantum efficiency of solids: Application to Nd3+-doped fluoride glass

Abstract

A multiwavelength thermal lens (TL) method was developed to determine the fluorescence quantum efficiency of solids. The experiments have been performed in Nd3+-doped fluoride glasses, using five different excitation wavelengths: 514, 576, 741, 796, and 867 nm. In this work, the absolute value of fluorescence quantum efficiency can be obtained by the linear dependence of the TL signal with the excitation wavelength. Our results suggest that the method can be applied to study a wide range of fluorescent materials, with a special ability to be used for measurements of highly transparent materials with very low TL effect.

Quantum yield excitation spectrum (UV-visible) of CdSe/ZnS core-shell quantum dots by thermal lens spectrometry

“…This method is named MW, and has been applied in liquids 8 and solids. 6 For dilute solutions, the parameter ⌰ o of the solution in general is practically the same as the pure solvent. In this case, the solvent parameter can be used in Eq.…”

“…Mainly two approaches based on TLS have been used for measurements in liquids and solids, 5,6 reference sample ͑RS͒ and multiwavelength ͑MW͒. In the first method, the thermaloptical properties of the sample must be known or else, the solvent of the solution ͑or the undoped matrix͒ with negligible fluorescence should be used as a reference.…”

“…5 The second routine ͑MW͒ can be used when is independent on the excitation wavelength in some wavelength range, which occurs usually for a broad absorption band like in rhodamine 6G, 8 or when all excited states decay very fast to a single emitting metastable level, which is the case of Nd 3+ and other rare earth ions. 6 In this case, where the nonradiative transitions are used as an internal reference, the thermaloptical parameters and are directly obtained from the dependence of the thermal lens ͑TL͒ signal with the excitation wavelength. Nowadays, the mode-mismatched dual-beam ͑pump-probe͒ TLS configuration is the most applied one.…”

“…However, the photothermal spectroscopy methods, as the thermal lens spectrometry ͑TLS͒, [1][2][3] has been shown to be an alternative way to obtain with accurate precision, [4][5][6][7][8] by measuring the fraction of absorbed energy converted into heat ͑͒ in the sample. The measurement of is complementary to the purely optical methods, such as PL and lifetime measurements.…”

Influence of temperature and excitation procedure on the athermal behavior of Nd3+-doped phosphate glass: Thermal lens, interferometric, and calorimetric measurements

“…[1][2][3][4][5][6][7][8][9][10] Either as highly transparent optical windows or mostly as host for luminescent ions. Optical glasses have also been used for high power lasers.…”