Novel Devices and Components Polarization-preserving teflon photonic crystal fiber waveguide for THz radiation

Abstract Using a highly flexible plastic material, Teflon, photonic crystal fiher (PCF) waveguide for THz radiation is constructed. It is found that such PCF possesses strongly polarizationpreserving property. With such feature, coupled with relatively low-loss coefficient, the possibility of preparing long PCF waveguide in the THZ region can be easily attained. Introduction The terahertz (THz) region that lies between the electronic and optical region in the electromagnetic spectrum, wit

All-solid-state tunable ultraviolet subnanosecond laser with direct pumping by the fifth harmonic of a Nd:YAG laser

We report what we believe is the first all-solid-state tunable ultraviolet laser pumped by the fifth harmonic of a Q-switched Nd:YAG laser. Our laser based on a Ce3+:LiLuF4 active medium stably generates a single, satellite-free, 0.88-ns pulse under 5-ns, 10-Hz repetition rate pumping conditions. A novel tilted-incident-angle side-pumping scheme resulted in a simple laser-cavity design. © 1998 Optical Society of America

All-solid-state subnanosecond tunable ultraviolet laser sources based on Ce3+-activated fluoride crystals

Several practical all-solid-state tunable ultraviolet subnanosecond laser sources have been developed based on Ce3+:LiLuF4 (Ce:LLF) and Ce3+:LiCaAlF6 (Ce:LiCAF) active media pumped by the fifth and fourth harmonics of a regular Q-switched 10-ns Nd:YAG laser, respectively. The demonstrated tuning range of the Ce:LiCAF oscillator providing reproducibly-single-pulse output was 282 nm to 314 nm with the maximum output energy of 1 mJ. Tunable laser output from 223 nm to 232 nm was obtained by sum-frequency-mixing Ce:LiCAF laser output with fundamental output of a Q-sw Nd:YAG laser. The maximum subnanosecond Ce:LiCAF single-pulse output of 14 mJ was obtained in a "master oscillator-power amplifier" (MOPA) configuration

Direct and passive subnanosecond pulse-train generation from a self-injection-seeded ultraviolet solid-state laser

We propose a passive self-injection-seeding scheme for the generation of short-pulse trains from various pulsed lasers. In this scheme a single subnanosecond pulse is generated from a short-cavity seeding laser. The pulse is then returned to the same gain medium and amplified regeneratively until the gain is quenched completely. Cw operation capability or an external short-pulse seeding laser is not required for generation of short-pulse trains. Based on this simple scheme an ultraviolet subnanosecond pulse train is directly and passively generated from a solid-state laser medium (Ce3+:LuLiF 4) pumped by a standard 10-ns laser. © 1995 Optical Society of America

Generation of ultra-short light pulses by a rapidly ionizing thin foil

A thin and dense plasma layer is created when a sufficiently strong laser pulse impinges on a solid target. The nonlinearity introduced by the time-dependent electron density leads to the generation of harmonics. The pulse duration of the harmonic radiation is related to the risetime of the electron density and thus can be affected by the shape of the incident pulse and its peak field strength. Results are presented from numerical particle-in-cell-simulations of an intense laser pulse interacting with a thin foil target. An analytical model which shows how the harmonics are created is introduced. The proposed scheme might be a promising way towards the generation of attosecond pulses. PACS number(s): 52.40.Nk, 52.50.Jm, 52.65.RrComment: Second Revised Version, 13 pages (REVTeX), 3 figures in ps-format, submitted for publication to Physical Review E, WWW: http://www.physik.tu-darmstadt.de/tqe

Subnanosecond tunable ultraviolet pulse generation from a low-Q, short-cavity Ce:LiCAF laser

We have developed an all-solid-state tunable ultraviolet laser system employing recently developed Ce:LiCAF, a new degradation-free tunable ultraviolet laser medium pumped by the fourth harmonic of a conventional Q-switched Nd:YAG laser. The low-Q, short-cavity Ce:LiCAF laser produced satellite-free subnanosecond pulses in a tuning range of 281 nm to 297 nm under appropriate pumping-fluence control

Ultraviolet short pulses from an all-solid-state Ce:LiCAF master-oscillator-power-amplifier system

We have developed an all-solid-state master-oscillator-power-amplifier system employing Ce:LiCAF, a new degradation-free tunable ultraviolet laser medium pumped by the fourth harmonic of conventional 10-ns Q-switched Nd:YAG lasers. The low-Q, short-cavity Ce:LiCAF master oscillator produced a satellite-free 1-ns pulse under appropriate pumping-fluence control. 18% energy extraction with sufficient gain was achieved in a single-stage, confocal, double-pass amplifier. As a result, 289-nm, 1-ns, 14-mJ pulses were efficiently obtained from this simple laser system. © 1997 Optical Society of America

Ultraviolet picosecond pulses from an all-solid-state Ce:Flouride master oscillator and power amplifier system

290-nm, 590-psec, 300-μJ pulses are obtained from a Ce:LiSAF/Ce:LiCAF MOPA system pumped by the fourth harmonic of a Nd:YAG laser

Ce3+-Activated Fluoride Crystals as Prospective Active Media for Widely Tunable Ultraviolet Ultrafast Lasers with Direct 10-ns Pumping

New possibilities have been investigated for recently developed solid-state tunable ultraviolet (UV) laser materials such as Ce+ ion-activated LuLiF4 (LLF) and LiCaAlF6 (LiCAF). With their broad-gain width, demonstrated reliability, and high efficiency, they are attractive for ultrashort pulse generation and amplification. To prove that, we have demonstrated UV picosecond-pulse amplification using Ce : LLF. For such new laser materials, we proposed a passive self-injection seeding scheme for the direct generation of short-pulse trains, which does not require CW-operation capability or an external short-pulse seeding laser. Using this simple scheme, a UV sub-nanosecond pulse train is directly and passively generated from Ce:LLF pumped by a standard 10-ns KrF excimer laser, and Ce : LiCAF pumped by the fourth harmonic of a conventional 10-ns Q -switched Nd : YAG laser. © 1995 IEE