Metasurfaces could be very beneficial when elaborating solar cells to succeed in balancing between cost and efficiency. Thus, thin absorbers achieving high performance are attainable with the possibility use any material. In this work, a perfect absorber based on tungsten (W) metal-insulator-metal (MIM) metasurface is proposed. The MIM array consists of rectangular double split ring resonator (...

The mechanical and optical arrangement of the 160-cm aperture, 90-m focal length, McMath Solar Telescope is described. Efforts have been made to obtain good images by thermal control of the optical paths and by selection of fused quartz or metal-based mirrors for the optical components. The optical paths and performances of a vacuum double-pass spectrometer and single-pass spectrograph are illu...

Aims. We present a method that allows us to estimate the distance from the continuum source located in the center of AGN to the highly ionized gas called warm absorber. Methods. We compute a set of constant total pressure photoionization models compatible with the warm absorber conditions, where a metal-rich gas is irradiated by a continuum in the form of a double power-law. The first power-law...

We demonstrate the operation of an ultra low repetition rate, high peak power, picosecond diode pumped Nd:YVO4 passively mode locked laser oscillator. Repetition rates even below 1 MHz were achieved with the use of a new design multiple-pass cavity and a semiconductor saturable absorber. Long term stable operation at 1.2 MHz, pulse duration of 16.3 ps and average output power of 470 mW correspo...

We demonstrate the generation of high-energy picosecond pulses directly from a thin-disk laser oscillator by employing a self-imaging active multipass geometry. Stable single-pulse operation has been obtained with an average output power in excess of 50 W, excluding a cw background of 8%, at a repetition rate of 3.8 MHz. Self-starting passive mode locking was accomplished using a semiconductor ...

We demonstrate the operation of an ultralow-repetition-rate, high-peak-power, picosecond diode-pumped Nd:YVO4 passively mode-locked laser oscillator. Repetition rates lower than 1 MHz were achieved with the use of a new design for a multiple-pass cavity and a semiconductor saturable absorber. Long-term stable operation at 1.2 MHz with a pulse duration of 16.3 ps and an average output power of 4...

Acoustic Absorber In article number 2201757, Gih-Keong Lau and co-workers report that a single type of absorber does not completely mitigate the variable noise whose frequency shifts with vehicle speed load. A transformable switches from Helmholtz resonance at medium to membrane low is developed. Electro-adhesive zip double micro-slit layers helps reduce effective hole ratio. This transparent c...