LAUSR

Abstract We aimed to investigate the influence of Er3+ rare earth element on the frequency conversion wavelength in boron doped GaSe crystals. It was found that by substitution of Er3+ with B3+, SHG signal shifted to higher wavelength. In addition, the nonlinear absorption properties and ultrafast dynamics of pure, 0.5 at% B3+ and 0.25 at% B3+ + 0.25 at% Er3+ doped GaSe crystals have been studied by open aperture Z-scan and ultrafast pump probe spectroscopy techniques. All of the studied crystals showed nonlinear absorption (NA). It was observed that 0.5 at% B3+ doped GaSe crystal showed bleach signal. This signal switched to NA signal with long life after substitution of 0.25 at% Er3+ with 0.25 at% B3+.