Roman Böttger

TL;DR: In this paper, the authors combine ion implantation with pulsed laser melting in a CMOS-compatible approach to introduce Te dopant into the Si crystal, at concentrations orders of magnitude above the solid solubility limit.

Abstract: Plasmonic Au nanoparticles embedded in LiNbO3 crystals as efficient saturable absorbers to realize 74.1 ps mode‐locked laser pulse generation at 1 µm are reported. The system is fabricated by Au ion implantation and subsequent annealing, a well‐developed chip technology. The strong optical absorption band peaking at 640 nm is observed due to the localized surface plasmon resonance. Z‐scan investigation shows that the LiNbO3 crystals with embedded Au nanoparticles possess ultrafast saturable absorption properties at near‐infrared 1 µm wavelength. With this feature the Au nanoparticles embedded LiNbO3 wafer is applied as saturable absorber into a laser‐written Nd:YVO4 waveguide platform. Stable laser pulses at 1064 nm based on an efficient passive Q‐switched mode‐locking process, reaching a fundamental repetition rate of 6.4 GHz and a pulse duration of 74.1 ps, are obtained. Since LiNbO3 has broadband applications in various optical systems, this work opens the way to develop intriguing devices in LiNbO3‐based photonic circuits by using embedded metallic nanoparticles.

TL;DR: In this article, the resistive switching properties of ion-exfoliated LiNbO3 thin films have been investigated and it was shown that the local filament does not penetrate throughout the thin film, resulting in asymmetric contact barriers at the two interfaces.

TL;DR: In this paper, the influence of localization on the hole-mediated ferromagnetism is examined in two DFSs with a differing strength of p-d coupling, and the results support the heterogeneous model of electronic states at the localization boundary and point to the crucial role of weakly localized holes in mediating efficient spin-spin interactions even on the insulator side of the metal-insulator transition.