The effect of Se/Te ratio on transient absorption behavior and nonlinear absorption properties of CuIn0.7Ga0.3(Se1-xTex)(2) (0 <= x <= 1) amorphous semiconductor thin films
Journal article, 2017

The characterization of the CuInSe2 (CIS), CuInGaSe (CIGS) and CuGaSe2 (CGS) based semiconductor thin films are very important role for solar cell and various nonlinear optical applications. In this paper, the amorphous CuIn0.7Ga0.3(Se1-xTex)(2) semiconductor thin films (0 <= x <= 1) were prepared with 60 nm thicknesses by using vacuum evaporation technique. The nonlinear absorption properties and ultrafast transient characteristics were investigated by using open aperture Z-scan and ultrafast pump-probe techniques. The energy bandgap values were calculated by using linear absorption spectra. The bandgap values are found to be varying from 0.67 eV to 1.25 eV for Culn(0.7)Ga(0.3)Te(2), Culn(0.7)Ga(0.3)Se(1.6)Te(0.4), Culn(0).7Ga0.3Se1-xTe1.6 and Culn(0.7)Ga(0.3)Se(2) thin films. The energy bandgap values decrease with increasing telluride (Te) doping ratio in mixed Culn(0.7)Ga(0.3)(Se1-xTex)(2) films. This affects nonlinear characteristics and ultrafast dynamics of amorphous thin films. Ultrafast pump-probe experiments indicated that decreasing of bandgap values with increasing the Te amount switches from the excited state absorption signals to ultrafast bleaching signals. Open aperture Z-scan experiments show that nonlinear absorption properties enhance with decreasing bandgaps values for 65 ps pulse duration at 1064 nm. Highest nonlinear absorption coefficient was found for Culn(0.7)Ga(0.3)Te(2) thin film due to having the smallest energy bandgap. (C) 2017 Elsevier B.V. All rights reserved.

laser

Materials Science

selenization

deposition

Ultrafast pump-probe

precursors

Amorphous thin films

tellurium te

Optics

growth

Z-scan

solar-cells

temperature

annealing

improved performance

Nonlinear absorption

Semiconductor

saturable-absorber mirror

Author

A. Karatay

Ankara Universitesi

Betül Kücüköz

Ankara Universitesi

G. Cankaya

Ankara Yıldırım Beyazıt University

A. Ates

Ankara Yıldırım Beyazıt University

A. Elmali

Ankara Universitesi

Optical Materials

0925-3467 (ISSN)

Vol. 73 NOV 20-24

Driving Forces

Sustainable development

Areas of Advance

Building Futures (2010-2018)

Subject Categories

Chemical Engineering

Chemical Sciences

DOI

10.1016/j.optmat.2017.07.046

More information

Latest update

5/21/2021