PbS(Se) Quantum Dot Doped Glass Applications as Laser Passive Q‐Switches

Abstract

A. M. Malyarevich 1 ) (a), V. G. Savitsky (a) I. A. Denisov (a), P. V. Prokoshin (a), Subject classification: 78.66.Jg; 78.67.Hc; S8.11; S8.12; S10.15 Nonlinear optical properties of phosphate and silicate glasses doped with PbS and PbSe quantum dots of different sizes were studied. Absorption saturation intensity in the range of the first and second excitonic transitions was estimated. Passive Q-switch operation of glasses doped with PbSand PbSe-quantum dots as saturable absorbers for 1.067 mm Nd 3+ : KGd(WO 4 ) 2 , 1.54 mm Er : glass and 2.1 mm Ho 3+ : Cr 3+ : Tm 3+ : Y 3 Al 5 O 12 diode-and flashlamp-pumped lasers was demonstrated.1. Introduction Glasses doped with semiconductor quantum dots (QDs) are being extensively studied as promising materials for various photonics applications. Recently passive Q-switch and mode-locking operation for both pulse and cw pumped lasers were presented at 0.7-0.9 mm with CdTe-doped glasses [1-3] and at 1.06-1.08 mm with CuInSSe-doped ones [4]. In the near infrared region PbS(Se) QDs are very attractive to be used as saturable absorbers. The reason is that PbS and PbSe have a large bulk exciton Bohr radius (a B 18 and 33 nm, respectively) and small energy bandgap (E g 0.41 and 0.28 eV, respectively) at room temperature, which allows to obtain the first absorption resonance in a wide spectral range from 3 down to 1 mm only by varying the QD size. Glass containing PbS QDs was successfully used as passive mode-locker for a Cr:forsterite laser at 1.2-1.3 mm [5].In this paper we present nonlinear optical properties of PbS and PbSe quantum dots in phosphate and silicate glasses and their applications for Q-switching of Nd:KGW (at 1.067 mm), Er:glass (at 1.54 mm) and Ho : YAG (at 2.1 mm) lasers with diode and flashlamp pumping.

Optical properties of PbSe quantum dots doped in borosilicate glass

“…Furthermore, the wavelengths of PL from theses quantum dots are located in the near-infrared region that can be used to amplify the optical signals for the communications [4]. Lead-salt QDs also can be applied to the infrared lasers [5] and solar cells [6].…”

Fluorophosphate glasses doped with PbSe quantum dots and their nonlinear optical characteristics

“…This feature determines the possibility of using glasses with quantum dots as Q-switches and mode locking elements, including mode locking devices for Kerr-lens mode-locked solid-state lasers. At present, glasses with quantum dots have already been used for generating short pulses by the lasers operating in the spectral ranges 0.7-0.9, 1.06-1.08, and 1.2-1.3 µ m [1][2][3]. However, glasses with quantum dots have not been used in the longer wavelength range.…”

“…Considerable interest in these objects is caused by their possible application in infrared optoelectronics in the spectral range 1-3 µ m. Recent investigations [1][2][3] have demonstrated that silicate glasses doped with quantum dots can be used as saturable absorbers for passive mode locking in solid-state lasers.…”

“…It should be noted that the temperature-time conditions providing for the formation of quantum dots in fluorophosphate glasses are considerably milder than those of silicate glasses, even though both types of glasses have relatively close values of the glass transition temperatures (450-480 ° C for silicate glasses [1] and 425 ° C for fluorophosphate glasses [1,6,7]). This circumstance is associated with the fact that the temperature dependences of the viscosity for the above classes of glasses exhibit a different behavior.…”

Optical waveguides in electrooptical nanophase glass–ceramics

“…However, these and other properties of glasses can be essentially modified if they are embedded with nanoscale crystalline inclusions. Depending on the inclusion composition and structure, such glassy materials behave similarly to crystalline ones and demonstrate effective saturable absorption [3] and optical limiting [4], high electrooptical [5] and optical [6] Kerr sensitivities, second harmonic generation [7,8], and enhanced rare-earth ion luminescence [9]. If these materials are transparent and allow formation of optical waveguides, they could be used to develop new types of integrated optics structures.…”