Ultranarrow bandwidth moiré reflecting Bragg gratings recorded in photo-thermo-refractive glass

Abstract

An experimental demonstration of a moiré reflecting Bragg grating in photo-thermo-refractive glass is carried out. This narrowband filter is obtained by the recording of two reflecting Bragg gratings with different periods. Filters with central wavelength at 1550 nm, bandwidth of 50 pm, and transmission higher than 95% are demonstrated. The methods to decrease bandwidth to 1 pm are finally investigated.

A review of the photo-thermal mechanism and crystallization of photo-thermo-refractive (PTR) glass

“…Ondax [11] and PD-LD [12]. PTR glass mainly allows for the production of four types of optical elements: transmitting Bragg gratings [13,14], reflecting Bragg gratings [15,16], chirped Bragg gratings [17,18] and phase plates [19,20]. Photosensitive fibers made out of PTR glass have also been reported [21].…”

Saturation of multiplexed volume Bragg grating recording

“…They are used for spectral combining of high-power laser beams [3][4][5], for stretching and compression of ultrashort pulses [6,7], for mode stabilization of diode lasers [8], for passive coherent beam combining [9], and for narrowband filtering in different fields of spectroscopy [10,11]. Many of these elements are multiplexed VBGs, that is, they contain several gratings with different spatial frequencies.…”

Effect of aberrations in a holographic system on reflecting volume Bragg gratings

“…Reflecting Bragg gratings (RBGs) are used as spectrally selective elements in a variety of applications including spectral beam combining [1,2], mode selection in lasers [3,4], and spectral filtering [4][5][6][7]. For applications requiring narrow spectral selectivity [8], or large apertures [9], these gratings must have a uniform period throughout the thickness of the recording medium, which may be on the order of millimeters, two orders of magnitude thicker than typical film gratings.…”