Feature issue introduction: optical ceramics

This feature offers 11 papers in the field of optical ceramics, and encompasses advances in optics, materials science, condensed matter, as well as physics and chemistry relevant to the development of new optical materials. Topics covered include material technologies in the field of polycrystalline ceramics, single crystals, and glass ceramics in the form of bulk and microstructured materials along with methods to fabricate the materials and a description of their optical properties pertinent for many applications

Efficient generation of highly squeezed light and second harmonic wave with periodically poled MgO:LiNbO_3

We report on effective generation of continuous-wave squeezed light and second harmonics with a periodically poled MgO:LiNbO$_{\mathrm{3}}$ (PPMgLN) crystal which enables us to utilize the large nonlinear optical coefficient $d_{\mathrm{33}}$. We achieved the squeezing level of $-7.60 \pm 0.15$dB at 860 nm by utilizing a subthreshol optical parametric oscillator with a PPMgLN crystal. We also generated 400 mW of second harmonics at 430 nm from 570 mW of fundamental waves with 70% of conversion efficiency by using a PPMgLN crystal inside an external cavity.Comment: 4 pages, 3 figure

Focus issue introduction: Advanced Solid-State Lasers (ASSL) 2014

The editors introduce the focus issue on Advanced Solid-State Lasers (ASSL) 2014, which is based on the topics presented at a congress of the same name held in Shanghai, China, from October 27 to November 1, 2014. This Focus issue, jointly prepared by Optics Express and Optical Materials Express, includes 28 contributed papers (21 for Optics Express and 7 for Optical Materials Express) selected from the voluntary submissions by attendees who presented at the congress and have extended their work into complete research articles. We hope this focus issue offers a useful snapshot of the variety of topical discussions held at the congress and will contribute to the further expansion of the associated research areas

Diode-Pumped Tunable Yb:YAG Miniature Lasers at Room Temperature: Modeling and Experiment

Abstract

Spectral Phase Control of Interfering Chirped Pulses for High-Energy Narrowband Terahertz Generation

Highly-efficient optical generation of narrowband terahertz (THz) radiation enables unexplored technologies and sciences from compact electron acceleration to charge manipulation in solids. State-of-the-art conversion efficiencies are currently achieved using difference-frequency generation (DFG) driven by temporal beating of chirped pulses but remain, however, far lower than desired or predicted. Here we show that high-order spectral phase fundamentally limits the efficiency of narrowband DFG using chirped-pulse beating and resolve this limitation by introducing a novel technique based on tuning the relative spectral phase of the pulses. For optical terahertz generation, we demonstrate a 13-fold enhancement in conversion efficiency for 1%-bandwidth, 0.361 THz pulses, yielding a record energy of 0.6 mJ and exceeding previous optically-generated energies by over an order of magnitude. Our results prove the feasibility of millijoule-scale applications like terahertz-based electron accelerators and light sources and solve the long-standing problem of temporal irregularities in the pulse trains generated by interfering chirped pulses.Comment: 25 pages, 5 figures, updated to the state before review at Nature Communications (updated the affiliations, title, some content, methods, etc.

Single Mode oscillation of Pulsed Solid-State Lasers by Injection Seeding

Single frequency and high power oscillation of solid state lasers have received much attention in recent years mainly because of the potential perfornancesin new coherent opto-electric applications. The injection seeding technique is useful method for single frequency operation of Q-switched lasers. In this paper，fundamental characteristics are analyzed on the injection seeding of solid state lasers using semiclassical theory. This method was tested using the LD pumped Nd:YVO4 micro-chip laser as a master laser to lock a Nd:YAG pulsed slave laser. A good agreement was obtained between theoretical and experimental results. A wide seeding spectral range of 59GHz and mode selection range of 282MHz was realized

A Polarization Control Method for Intra-Cavity Frequency Doubling of Q-switch Nd:YAG Lasers with KTP Crystals

In effcient frequency doubling (SHG) of the Q-switch Nd:YAG laser，a biaxial nonlinear crystal like KTP(Potassium Titanyl Phosphate) is mostly used inside the laser cavity with the quarter wave plate to adjust the laser beam polarization angle. In this paper，a new technique has been developed for controlling the laser beam polarization without the wave plate by adjusting the angles of the biaxial KTP crysta1. The refractive index of the biaxial nonlinear crystal was analyzed using the Jones Matrix. This method was testedusing the Q-switch Nd: YAG laser and a good agreement was obtained between theoretical and experimental polarization data. A high effective conversion efficiency of 84% was realized from 1064 nm to 532 nm beam at 1 kHz pulse repetition frequency