Nikolay Primerov - Academia.edu (original) (raw)

Papers by Nikolay Primerov

Reflections from movable, dynamic acoustic gratings in polarization maintaining (PM) fibers are e... more Reflections from movable, dynamic acoustic gratings in polarization maintaining (PM) fibers are employed in the long variable delay of periodic, isolated pulses. The gratings are introduced by stimulated Brillouin scattering (SBS) interaction between two counter-propagating pump waves, which are spectrally detuned by the Brillouin frequency shift of the PM fiber and are both polarized along one of its principal axes. The gratings are interrogated by the reflections of read-out signals that are polarized along the orthogonal principal axis. High-rate phase modulation of both pump waves by a pseudo-random binary sequence introduces dynamic gratings that are both localized and stationary, at specific locations in which the modulated pumps are correlated. The separation between adjacent correlation peaks can be made arbitrarily long. Long variable delays are readily obtained by scanning the grating along the fiber, via changing either the length or the rate of the modulation sequence. At the same time, the short length of the gratings, on the order of a cm, accommodates the delay of broadband pulses. The technique is therefore free of the delay-times-bandwidth product limitation that undermines the performance of SBS-based 'slow light' delay: we report the delay 1-ns long pulses by as much as 770 ns. In addition, the combined reflections from two dynamic gratings with a variable separation are used to implement radio-frequency photonic filters of tunable free spectral range. At the current stage, the technique is restricted by noise from residual scattering that takes place outside of the correlation peaks. Hence, it is thus far limited to the processing of repetitive signals, for which the noise may be effectively averaged out.

We demonstrate the first fiber-coupled, broadband master oscillator power amplifier (MOPA) module... more We demonstrate the first fiber-coupled, broadband master oscillator power amplifier (MOPA) module where amplified spontaneous emission (ASE) light from an 840-nm superluminescent diode (SLED) is amplified by a low-confinement, broadband 840-nm semiconductor optical amplifier (SOA), generating power levels of more than 60 mW in single-mode fibers. The SLED and SOA are integrated, without an optical isolator in between, in a compact 14-pin Butterfly module on a temperature-stabilized optical bench. The highly-polarized ASE output has a polarization extinction ratio (PER) of more than 30 dB and a 10-dB bandwidth of more than 50 nm, resulting in a coherence length of 10 microns in air.

We demonstrate a 1300-nm ultra-broadband and compact light source module with 180 nm FWHM optical... more We demonstrate a 1300-nm ultra-broadband and compact light source module with 180 nm FWHM optical bandwidth and 22 mW of output power, realized with four superluminescent diodes (SLEDs) that are integrated on a temperaturestabilized, free-space, micro-optical bench in a standard 14-pin Butterfly package. The light output of four SLED chips at 1220 nm, 1270 nm, 1310 nm and 1360 nm is collimated by micro-optical collimation lenses, spectrally combined through free-space dielectric edge filters and focused into a SMF-28 single-mode fiber. The combined broadband spectrum corresponds to a coherence length of 5.4 μm in air, suitable for ultra-high-resolution OCT systems at 1300 nm.

Proceedings of SPIE, May 15, 2011

Stimulated Brillouin scattering (SBS) amplification of probe signals is highly polarization depen... more Stimulated Brillouin scattering (SBS) amplification of probe signals is highly polarization dependent. Maximum and minimum gain values are associated with a pair of orthogonal states of polarization (SOP) at the fiber output. Since the maximum gain is much higher than the minimum, the output probe SOP is pulled towards that of the maximum amplification. Polarization pulling is restricted, however, by pump depletion. In this work, we propose, analyze and demonstrate a method for enhanced SBS polarization pulling, using two orthogonal pumps: the one amplifies the probe wave whereas the other attenuates it. The method provides the same polarization pulling as that of a single amplifying pump, however it is considerably more tolerant to depletion.

Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXVII

Digital Optical Technologies 2019

We present the first light source module that is realized with RGB superluminescent LEDs in a com... more We present the first light source module that is realized with RGB superluminescent LEDs in a compact 14-pin butterfly housing for speckle-free display applications. The module provides a free-space output with collimated RGB beams that are colinearly aligned having 10 mW output power per color.

Digital Optical Technologies 2021

We demonstrate a miniaturized, full-color RGB light source module for near-to-eye display systems... more We demonstrate a miniaturized, full-color RGB light source module for near-to-eye display systems, incorporating three semiconductor laser diodes (LDs) that are integrated on a free-space, micro-optical bench together with collimation optics and wavelength filters. The ultra-compact package has a footprint of 4.4 mm x 4.15 mm with a height of 2.9 mm (0.053 cm3) and an optical output window for the collimated and collinearly aligned RGB beams. The light source module delivers up to 10 mW per color at low power dissipation values of 640 mW and provides low-divergent output beams having a high circularity and a diameter of 250-650 μm at a reference distance of 50 mm.

We demonstrate a novel light source for multi-modality imaging where three superluminescent diode... more We demonstrate a novel light source for multi-modality imaging where three superluminescent diodes (SLEDs) are integrated on a free-space, temperature-stabilized, micro-optical bench in a standard 14-pin butterfly package. The light output of the three SLED chips is collimated by individual micro-optical collimation lenses and then spectrally and spatially combined in free space through dielectric edge filters before being coupled into a common HI-780 single-mode output fiber. The two SLEDs at 840 nm and 880 nm deliver a combined broadband spectrum with 120 nm bandwidth and 8.5 mW of output power for ultra-high-resolution optical coherence tomography (OCT) imaging with an axial resolution of ~4 microns in air. The third SLED at 750 nm is suitable for implementing eye tracking based on a scanning laser ophthalmoscope (SLO). Because of the free-space architecture, the polarization of all SLEDs is intrinsically aligned such that the UHR-OCT broadband source has a high PER of 20 dB acro...

We demonstrate an 840-nm broadband and compact light source with 140 nm FWHM optical bandwidth an... more We demonstrate an 840-nm broadband and compact light source with 140 nm FWHM optical bandwidth and 8 mW of output power, realized with three superluminescent diodes (SLEDs) that are, to our knowledge for the first time, integrated on a free-space, micro-optical bench in a standard 14-pin butterfly package. The three SLED chips at 790 nm, 840 nm and 880 nm are mounted on a ceramic baseplate that is temperature-stabilized by a thermo-electric cooler. The light output of the SLEDs is collimated by micro-optical collimation lenses, spectrally combined through free-space dielectric edge filters and focused into a HI-780 single-mode fiber. The combined broadband spectrum corresponds to a coherence length of 2.9 μm in air, suitable for ultra-high-resolution OCT systems.

Optical fibre sensors based on stimulated Brillouin scattering have now clearly demonstrated thei... more Optical fibre sensors based on stimulated Brillouin scattering have now clearly demonstrated their excellent capability for long-range distributed strain and temperature measurements. The fibre is used as sensing element and a value for temperature and/or strain can be obtained from any point along the fibre. While classical configurations have practically a spatial resolution limited by the phonon lifetime to 1 meter, novel approaches have been demonstrated these past years that can overcome this limit. This can be achieved either by the prior activation of the acoustic wave by a long lasting pre-pumping signal, leading to the optimized configuration using Brillouin echoes, or by probing a classically generated steady acoustic wave using a ultra-short pulse propagating in the orthogonal polarization of a highly birefringent fibre. These novel configurations can offer spatial resolutions in the centimetre range, while preserving the full accuracy on the determination of temperature ...

A novel technique to realize true time reversal of an optical signal, using dynamic Brillouin gra... more A novel technique to realize true time reversal of an optical signal, using dynamic Brillouin gratings in high-birefringence fibers, is proposed. A data sequence of optical pulses with 2-ns duration was efficiently time-reversed. A numerical simulation of the process confirmed the experimental results.

SID Symposium Digest of Technical Papers

2011 Conference on Lasers and Electro-Optics Europe and 12th European Quantum Electronics Conference (CLEO EUROPE/EQEC), 2011

Recently, all-optical multiplication techniques of the repetition rate of optical pulse trains ha... more Recently, all-optical multiplication techniques of the repetition rate of optical pulse trains has been actively searched using a variety of mechanisms, i.e. spectral filtering , spatial Talbot effects and micro-cavity structures since it is believed to be a promising solution for ultrafast transmission in optical communication systems and optical signal processing. We here propose an entirely different approach for realizing the multiplication of the pulse repetition rate with a flexibly tunable multiplication factor. Actually, this technique is based on an all-fiber configuration, which renders the system very attractive for future applications in optical communications. This system makes use of dynamic Brillouin grating (DBG) reflectors implemented in highly birefringent fibers, and the repetition rate of a pulse train is readily reconfigurable by simply changing the number of dynamic grating reflectors positioned in the fiber.

Advances in Slow and Fast Light V, 2012

Stationary and localized Brillouin dynamic gratings are generated using phase modulation of both ... more Stationary and localized Brillouin dynamic gratings are generated using phase modulation of both pump waves by a pseudo-random bit sequence. The gratings are applied to long variable delay of pulses and to cm-level distributed sensing.

Optical Fiber Communication Conference, 2010

We experimentally demonstrate a novel technique to realize a tunable delay line based on dynamic ... more We experimentally demonstrate a novel technique to realize a tunable delay line based on dynamic Brillouin gratings in a high birefringence fiber. A 8ns pulse signal is continuously delayed up to 184ns with minor distortion. Fig. 3. (a) Selected signal waveforms for different true delays. (b) Measured time delays of the back-reflected signal pulse as a function of the delay set for pump 1 pulse and the red line represents the linear fitting. a1767_1.pdf OSA / OFC/NFOEC 2010 OWF6.pdf

Advanced Photonics, 2011

We experimentally demonstrate that all-optical signal calculus can be realized based on dynamic B... more We experimentally demonstrate that all-optical signal calculus can be realized based on dynamic Brillouin gratings in fibers. Temporal integration and first-order differentiation were performed for optical pulse with various waveforms.