Properties of Ge_xAs_ySe_1-x-y glasses for all-optical signal processing

Abstract

We present a systematic study of Ge(x)As(y)Se(1-x-y) bulk chalcogenide glasses to determine the best composition for fabricating all-optical devices. The dependence of physical parameters such as the band-gap, glass transition temperature and third order optical nonlinearity (n(2)) on composition has been studied and a relation between the bond-structure and elevated linear loss levels in high Germanium glasses has been identified. It is found that glasses with 11<x<13 % are most suitable for all-optical devices.

Short range order in Ge–As–Se glasses

“…For example, the nonlinear refractive index n 2 of the Ge-As-Se glasses plotted as a function of the mean coordination number exhibits a minimum at the MCN values of about 2.7-2.8 [44] (Fig. 7a).…”

“…The physical properties of Ge-As-Se glasses have been shown to vary remarkably with either the Ge-concentration or the theoretical mean coordination number [43,44]. For example, the nonlinear refractive index n 2 of the Ge-As-Se glasses plotted as a function of the mean coordination number exhibits a minimum at the MCN values of about 2.7-2.8 [44] (Fig.…”

Laser Desorption Ionization Time‐of‐Flight Mass Spectrometry of Glasses and Amorphous Films from Ge–As–Se System

“…5,6 . Physical properties of bulk Ge-As-Se glasses were heavily reported: linear and nonlinear optical properties, [7][8][9][10][11] structure, 8,9,12 photoinduced processes, 13 etc. Fabrication and characterization of amorphous Ge-As-Se thin films was subject of deep research in last decade; pulsed laser deposition (PLD), [14][15][16][17][18] thermal evaporation 6,14,[19][20][21][22] or radio-frequency magnetron sputtering 23 were shown to be suitable deposition techniques; each of them possessing its own advantages and disadvantages.…”

Structural and physical properties of Ge 11.5 As 24 S 64.5·x Se 64.5·(1−x) glasses

“…Generally, the addition of Ge with 4-fold bond coordination compared with As (3-fold) and S/Se (2-fold) produces a more 3-dimensional glass network and this increases T g , and the tuneable properties in more broad range can be expected in ternary glasses [1,2]. Recently, Ge-As-Se glasses with an optical nonlinearity that is hundreds or thousands times than SiO 2 glasses have been reported [5,6]. Moreover, our on-going effort on searching stable glass compositions in Ge-As-Se systems has demonstrated that, the glasses with MCNs around 2.45-2.5 have strong glass-forming ability and less photosensitivity [7,8].…”

“…It was expected that S-based glasses are more durable against laser irradiation compared with Se-based glasses since the bond energy of S-S is larger than that of Se-Se [10], but substitution of S for Se shifts the bandgap from the infrared towards the visible and this can cause a decrease of the third order nonlinearity in the 1550 nm telecommunication band [5]. In terms of elemental chemistry, it is interesting to understand how the elemental substitution of S for Se can tune the properties of the glasses.…”