A high-power, low-noise photodetector, in conjunction with a current shunt actuator, is used in an ac-coupled servo to stabilize the intensity of a 10-W cw Nd:YAG laser. A relative intensity noise of 1 x 10(-8) Hz(-1/2) at 10 Hz is achieved.

We present a highly coherent semiconductor laser device formed by a 1⁄2-VCSEL structure and an external concave mirror in a millimetre high finesse stable cavity. The quantum well structure is diode-pumped by a commercial single mode GaAs laser diode system. This free running low noise tunable single-frequency laser exhibits >50mW output power in a low divergent circular TEM beam with a spectra...

Beam-driven plasma wakefield acceleration using low-ionization-threshold gas such as Li is combined with laser-controlled electron injection via ionization of high-ionization-threshold gas such as He. The He electrons are released with low transverse momentum in the focus of the copropagating, nonrelativistic-intensity laser pulse directly inside the accelerating or focusing phase of the Li blo...

introduction: low back pain (lbp) is the most common musculoskeletal disease. monochromatic infrared photo energy (mipe) and low level laser therapy (lllt) are light modalities used to reduce pain and increase blood flow. the aim of this study was to compare the effects of the mipe and lllt in reducing functional disability and pain as well as improving lumbar range of motion (rom) in patients ...

We propose a new accelerating concept, the chirpedpulse inverse free-electron laser (CPIFEL). We study the inverse free-electron laser (IFEL) accelerator both theoretically and computationally, and show that by using a femtosecond (fs), ultra-high-intensity drive laser pulse, the IFEL interaction bandwidth and accelerating gradient are increased, thus yielding large energy gains. Using a chirpe...

We calculate the binding energy of on- and off-center hydrogenic impurities in a parabolic quantum dot subjected to an intense high-frequency laser field. An exactly solvable model that replaces the actual Coulomb interaction with the donor by a non-local separable potential is introduced for calculating the binding energy. The separable potential allows us to solve the problem exactly and all ...

A second-generation pulse-burst laser system for high-speed flow diagnostics is described in detail. The laser can produce a burst of high-energy pulses (of the order of hundreds of millijoules per pulse) with individual pulse durations of less than 10 ns and pulse separations as short as 1 micros. A key improvement is the addition of a phase-conjugate mirror, which effectively isolates the hig...

Below TCO = 157 K the quasi-one-dimensional charge-transfer salt (TMTTF)2SbF6 undergoes a pronounced phase transition to a charge-ordered ground state. We have explored the non-linear and photoconductive behavior as a function of applied voltage, laser pulse energy and temperature. Besides a decay of the photoconductive signal in a double exponential fashion in the millisecond range, we discove...