Virtual Journal of Laser

D. D. Mai, J. Hallmann, T. Reusch, M. Osterhoff, S. Düsterer, R. Treusch, A. Singer, M. Beckers, T. Gorniak, T. Senkbeil, R. Dronyak, J. Gulden, O. M. Yefanov, A. Al-Shemmary, A. Rosenhahn, A. P. Mancuso, I. A. Vartanyants, T. Salditt
The spatial coherence of free-electron laser radiation in the water window spectral range was studied, using the third harmonic (λ_3rd = 2.66 nm) of DESY’s Free-electron LASer in Hamburg (FLASH). Coherent single pulse diffraction patterns of ... [Opt. Express 21, 13005-13017 (2013)]

Gaoming Li, Yishen Qiu, Hui Li
Abstract: We present the general coherence theory for laser beams passing through a moving diffuser. The temporal coherence of laser beams passing through a moving diffuser depends on two characteristic temporal scales: the laser coherence time and the mean time it takes the diffuser to move past a ... [Opt. Express 21, 13032-13039 (2013)]

Shuanghong Ding, Meiqin Wang, Shiwu Wang, Wenhui Zhang
The compact LD end-pumped passively Q-switched c-cut Nd:YVO_4/Cr^4+:YAG self-Raman laser is realized, and its output performance is investigated in detail. The maximum average output power at 1178nm is 800mW with the pulse repetition frequency of 44kHz and pulse width of 2.6ns, and the first Stokes ... [Opt. Express 21, 13052-13061 (2013)]

O. Benavides, L. de la Cruz May, A. Flores Gil
A comparative study on reflection of nanosecond Nd-YAG laser pulses in ablation of aluminum in air and in vacuum under the same other experimental conditions is performed. We find that, hemispherical total reflectivity of aluminum undergoes a sharp drop at the plasma formation threshold both in the ... [Opt. Express 21, 13068-13074 (2013)]

Joseph E. Vornehm, Aaron Schweinsberg, Zhimin Shi, Daniel J. Gauthier, Robert W. Boyd
Phase control is crucial to the operation of coherent beam combining systems, whether for laser radar or high-power beam combining. We have recently demonstrated a design for a multi-aperture, coherently combined, synchronized- and phased-array slow light laser radar (SLIDAR) that is capable of ... [Opt. Express 21, 13094-13104 (2013)]

Hiroaki Furuse, Haik Chosrowjan, Junji Kawanaka, Noriaki Miyanaga, Masayuki Fujita, Yasukazu Izawa
The amplified spontaneous emission (ASE) and parasitic lasing (PL) effects in thin disk laser with an anti-ASE cap have been investigated in detail by measuring both time-resolved radiated intensity at longer axis of elliptical pump profile (dominant ASE direction) and small signal gain (SSG) in ... [Opt. Express 21, 13118-13124 (2013)]

Fei Tian, Jiri Kanka, Bing Zou, Kin Seng Chiang, Henry Du
Long-period gratings (LPGs) inscribed in endlessly single mode (ESM) photonic crystal fibers (PCFs) with symmetric and asymmetric CO_2 laser irradiation are investigated both numerically and experimentally. Parallel results from conventional single mode fibers (SMFs) are presented for comparison. ... [Opt. Express 21, 13208-13218 (2013)]

S.G. Wang, J.W. Zhang, K. Miao, Z.B. Wang, L.J. Wang
We have developed a microwave frequency standard based on the 15.2 GHz ground-stated hyperfine transition of ^113Cd^+ ions. Using a laser-cooled ion cloud trapped in a linear quadrupole Paul trap, the clock transition frequency is measured to be 15 199 862 855.0125(87) Hz, with an accuracy at the ... [Opt. Express 21, 12434-12442 (2013)]

Yohei Kobayashi, Nozomi Hirayama, Akira Ozawa, Takashi Sukegawa, Takashi Seki, Yoshiyuki Kuramoto, Shuntaro Watanabe
Large-scale transmission gratings were produced for a stretcher and a compressor in the Yb-fiber chirped-pulse amplification system. A 23-W, 200-fs laser system with a 10-MHz repetition rate was demonstrated. Focused intensity as high as 10^14 W/cm^2 was achieved, which is high enough for ... [Opt. Express 21, 12865-12873 (2013)]

X. Liu, J-M. Mérolla, S. Guérandel, E. de Clercq, R. Boudot
We report on the detection of high-contrast and narrow Coherent Population Trapping (CPT) Ramsey fringes in a Cs vapor cell using a simple-architecture laser system. The latter allows the combination of push-pull optical pumping (PPOP) and a temporal Ramsey-like pulsed interrogation. An originality ... [Opt. Express 21, 12451-12459 (2013)]