Dmitri Kuksenkov

• Doctor of Philosophy
• Senior Research Associate at Corning Incorporated

In this paper we present the results of development of a backlight in which a single glass plate serves as both a light guide and a core of the printed circuit delivering current to the mini‐LED light sources. The backlight integrates a patterned glass diffuser (PGD) and a glass printed circuit board (GCB). The integrated backlight has the advantag...

We report on the design and performance of a direct‐lit LCD backlight prototype which is only 5 mm thick and capable of full array 2D local dimming. Equipped with a 15.6” LC display panel, the prototype reaches peak brightness of 2000 nits. The measured contrast numbers meet VESA DisplayHDR 600 specification.

The vast majority of light-emitting diode and liquid-crystal displays, solar panels, and windows in residential and industrial buildings use glass panels owing to their high mechanical stability, chemical resistance, and optical properties. Glass surfaces reflect about 4-5% of incident light if no antireflective coating is applied. In addition to e...

A novel design and application technique for light extraction in OLED displays are described, using micro‐optic patterns formed on the underside of an encapsulation glass. The design produces negligible haze and is fully compatible with the use of circular polarizers. A relative increase in brightness of 56% is demonstrated for a mobile phone displ...

We report on an ultra‐thin 2D local dimming backlight, as thin as an edge‐lit backlight, yet as capable of 2D local dimming as a direct‐lit backlight. It includes a patterned holey glass light guide plate (LGP) and a patterned reflector. Light from LEDs, located in holes, is edge‐coupled into the LGP.

Coring Iris™ Glass is a new high transmission glass for LCD back lighting applications. This paper reviews its mechanical and optical properties, contrasts them with polymeric materials currently in use, and demonstrates its benefit in ultra-slim LCD TV applications.

Rate equations analysis, supported by travelling wave simulations, is used to show that a diode laser design with a very low (<1%) confinement factor is optimal for generating streams of high energy optical pulses for nonlinear applications by large-signal modulation with both existing and potentially improved ac current generators. An asymmetric w...

A few mode optical fiber comprising: a Ge-free core having an effective area Aeff of LP01 mode wherein 120 μm2<Aeff<1000 μm2 at 1550 nm, and a refractive index profile selected such that the core is capable of supporting the propagation and transmission of an optical signal with X number of LP modes at 1550 nm, X is an integer and 1<X≦20, maximum...

An optical fiber comprising: (i) a core having a refractive index profile; (ii) an annular cladding surrounding the core; (iii) a primary coating contacting and surrounding the cladding, the primary coating having an in situ modulus of less than 0.35 MPa and an in situ glass transition temperature of less than −35° C.; and (iv) a secondary coating...

We have fabricated, to our knowledge, the first rectangular cross-section multicore fiber with eight cores arranged in a line. We have shown that the rectangular cross-section remains practically unchanged during the fiber-drawing process. The heterogeneous version of the proposed fiber design could be beneficial for crosstalk reduction because of...

The wavelength tunable 1060-nm distributed Bragg reflector (DBR) laser chip consists of three sections: a gain section for lasing, and phase and DBR sections for wavelength control. A micro-heater is lithographically integrated on the top of the DBR section to tune the emission wavelength. The phase section is designed with either a top heater or b...

We investigate transmission of 112 Gb/s PM-QPSK signals over 50 μm core diameter OM3 multimode fiber using the center launch approach. We demonstrate successful transmission of 16 DWDM channels over a distance of 635 km for a capacity-distance product of 1016 Tb/s-km. The limiting impairment appears due to mode coupling and multipath interference e...

We demonstrate a frequency-converted green laser source simultaneously emitting three spectral lines with nearly equal intensity and ~ 0.5 nm separation, enabling a factor of √3 reduction of speckle contrast in pico-projector applications. The source consists of an external cavity 1060 nm diode laser pump with dual-wavelength reflection provided by...

We investigate transmission of 112 Gb/s PM-QPSK signals over 50 μm core diameter OM3 multimode fiber using the center launch approach. We demonstrate successful transmission of 16 DWDM channels over a distance of 635 km.

Design and experimental testing results are presented for frequency doubled green laser source using diode laser pump in folded external cavity with bulk diffraction grating mirror used both for adaptive cavity alignment and wavelength selection.

Third harmonic (TH) generation by four-wave mixing is investigated in a novel design optical fiber. Numerical modeling predicts that TH conversion efficiency of > 50% is achievable in the proposed fiber design. Experimentally demonstrated TH conversion efficiency is 2.5%. The main causes for lower than expected conversion efficiency are studied.

An all-silica photonic bandgap fiber with a cladding index difference of approximately 2 % and diameter-to-pitch ratio (d/Λ) of 0.12 was fabricated and studied. To our knowledge, this is the first report on the properties of photonic bandgap fiber with such a small d/Λ. The fiber is single-mode in the fundamental bandgap. The mode field diameter in...

We present all-solid bandgap fiber design with the small ratio of cladding elements diameter to pitch (0.24), with MFD of 36 m at 1 m wavelength and higher order mode suppression caused by the propagation loss difference.

We report on the design and performance of an injection-seeded single-pass cascaded fiber Raman laser producing 10.5W average output power at 1172nm. The linewidth is < 0.1nm and optical to optical conversion efficiency is 35%.

We report on the design and performance of an injection-seeded single-pass cascaded fiber Raman laser producing 10.5 W average output power at 1172 nm. The linewidth is < 0.1nm and optical to optical conversion efficiency is 35%.

We propose an all-fiber based approach to scramble and un-scramble optical signal for secure fiber optic communications. A scrambler and un-scrambler pair with an operation range from 0.8 Gb/s to 1.4 Gb/s was demonstrated.

In this paper, we studied SC generation in fiber lasers and in optical fibers pumped by different light sources which include fs and ps pulse sources, and continuous-wave (CW) amplified spontaneous emission (ASE) light sources. First, we demonstrated SC generation with a 10dB spectral bandwidth of 430nm in a fiber ring laser with conventional nonli...

An iterative approach to modeling thermal lensing in χ2frequency conversion processes is described. Careful consideration is given to ensuring consistency of approximations. We find piezo-optic effects can partially compensate the impact of thermal dispersion.

We experimentally demonstrated continuous tuning of the wavelength of pulses of a subpicosecond soliton laser working in the 1.55 μm spectral range during propagation in a nonlinear optical fiber. The width of the tuning band reached 250–300 nm, and the maximum wavelength of solitons at the fiber exit exceeded 1.8 μm at an average optical power of...

A wavelength tunable stretched-pulse mode-locked all-fiber ring laser using single polarization fiber (SPF) was demonstrated. In this laser, a segment of SPF was used simultaneously as a polarizer and a tunable filter in the laser cavity. Self-starting mode-locking with femtosecond output pulses was demonstrated. A wavelength tuning of ~20nm was ac...

We propose a new and efficient approach to generation of a continuous-wave supercontinuum in optical fiber pumped by an amplified spontaneous emission light. A bandwidth of 268 nm (at -15 dB level) with an average spectral density of 2.7 mW/nm is demonstrated

Without using any additional SBS suppression means, 40 GHz 33% RZ pulse train generated by external modulation of a DFB laser diode output was successfully compressed to high-quality 1.3 ps transform-limited soliton pulses using adiabatic soliton compression in 5.45 km long DDF with high SBS threshold. Using the same fiber, as short as 870 fs low-p...

Operating principles and experimental testing results are reviewed for several multiple-WDM channel nonlinear fibre devices: optical clock recovery, 2R regenerator and dynamic residual dispersion compensator.

We report a self-starting stretched-pulse mode-locked all-fiber erbium ring laser with high output pulse energy. In this laser, to increase the output pulse energy a piece of positive-dispersion singlemode fiber with large core diameter is used to lower the nonlinearity in the positive dispersion section of the laser cavity. Pulses with ~0.6 nJ sin...

Dynamic dispersion compensation based on non-linear self-phase modulation (SPM) in an all-fiber device is demonstrated. The basic design of the compensator is very simple, consisting only of a pre-compensating negative dispersion fiber, an optical amplifier, and a highly non-linear positive dispersion fiber. Multiple channel operation of the compen...

Index profile grading and elimination of the central dip have yielded the lowest loss ever reported for modified chemical vapor deposition-made highly GeO₂-doped single-mode fibers (1.33 dB/km at 1550 nm for Δ=2.9%). Investigation of the angular distribution of scattering has shown that much of the optical loss in such fibers is due to a...

We propose a novel dispersion monitoring method based on four-wave mixing (FWM) or parametric amplification effect in optical fiber. The signal pulse stream, which is used as a parametric pump, is mixed with a weak continuous wave light at a different wavelength in a fiber. Due to the FWM effect, a so-called idler light is created at a wavelength s...

In this paper we report on the design, numerical simulation and experimental testing of a novel dynamic dispersion compensation device based on self-phase modulation (SPM) in nonlinear fiber. The proposed all-fiber device is inherently simple and presents several unique advantages, most notably the potential for a broad-band operation covering all...

Simultaneous dynamic dispersion compensation (130 ps/nm range) and 2R regeneration (2 dB receiver sensitivity improvement) are demonstrated for a 40 Gb/s CS-RZ signal using soliton effect pulse compression and narrowband spectral filtering.

A novel dispersion monitoring method based on four-wave mixing in fiber was proposed and experimentally demonstrated using 40 Gb/s RZ signal. This scheme potentially works for data rates up to Tbit/s.

Single-mode semiconductor pumps have failed to keep pace with the increasing power requirements of Er-doped fiber amplifiers (EDFAs), so there is a need for high-powered 980-nm sources. Yb3+-doped tapered fiber lasers can provide high-power output by conversion of a low-brightness, high-powered, 920-nm, multimode broad stripe laser diode to a high-...

Single-mode semiconductor pumps have failed to keep pace with the increasing power requirements of Er-doped fiber amplifiers (EDFAs), so there is a need for high-powered 980-nm sources. Yb3+-doped tapered fiber lasers can provide high-power output by conversion of a low-brightness, high-powered, 920-nm, multimode broad stripe laser diode to a high-...

A novel all-glass Yb-doped double-clad fibre laser that emits over 1 W of single-transverse-mode output at 978 nm is described. This device is efficiently pumped with 2.5 W of launched power from a single 200 μm broad-area laser diode at 915 nm

Small-signal impedance characteristics of quantum-well laser structures are analyzed. A simple analytical expression for the frequency dependence of below-threshold small-signal impedance is derived and verified experimentally. It is shown that the differential carrier lifetime and quantum-well transport and capture times can be extracted from elec...

A single-mode Yb fiber laser delivering 450 mW at 978 nm is reported. The device consists of a tapered multimode Yb fiber pumped with a 2 W 920 nm broadstripe. The pumping scheme has advantages over double-clad fiber lasers when applied to 3-level laser systems

Single-mode operation from an index-guided vertical-cavity surface-emitting laser (VCSEL) has been achieved by using a fiber Bragg grating (FBG) as an external selective wavelength reflector. The spectral characteristics of the external cavity controlled VCSEL under static and dynamic conditions have been studied. The FBG provided stable single mod...

This paper discusses a high-brightness multi-laser source developed at Polaroid for such applications as coupling light to fibers, pumping fiber lasers, pumping solid state lasers, material processing, and medical procedures. The power and brightness are obtained by imaging the nearfields of up to eight separate multi-mode lasers side by side on a...

Differential carrier lifetime measurements were performed on index-guided oxide-confined vertical cavity surface emitting lasers operating at 980 nm. Lifetimes were extracted from laser impedance measurements at subthreshold currents, with device size as a parameter, using a simple small-signal model. The carrier lifetimes ranged from 21 ns at 9 μA...

Summary form only given. Differential carrier lifetimes of index-guided oxide-confined (980 nm) vertical cavity surface-emitting lasers (VCSELs) were obtained from laser impedance measurements at subthreshold currents and equivalent circuit modeling

The authors report low-frequency noise measurements of doped-channel AlGaN-GaN heterostructure field-effect transistors grown on insulating silicon carbide substrates. In the frequency range 1 Hz-100 kHz the observed noise is of the 1/f type, and the estimated value of the Hooge constant α_H is ~10^-3

We report low-frequency noise characteristics of doped-channel GaN/AlGaN heterostructure field-effect transistors grown on sapphire substrates. In the frequency range 1 Hz-100 kHz the observed noise is of the 1/f character. The Hooge constant is of the order of 10/sup -2/ and is linearly proportional to the channel width. The noise originates in th...

Measurements of differential carrier lifetimes on gain-guided proton-implanted vertical-cavity surface-emitting lasers with device size as a parameter are reported. The lifetimes were obtained from laser impedance measurements and from small-signal modulation optical response at subthreshold currents. A simple small-signal equivalent circuit was us...

We study the origins of conductivity and low-frequency noise in GaN p-n junctions under reverse bias. Carrier hopping through defect states in the space charge region is identified as the main mechanism responsible for low bias conductivity. Threading dislocations appear the most likely source of such defect states. At higher bias hopping is supple...

We report solar-blind Al _x Ga _1-x N photovoltaic detectors with cutoff wavelengths as short as 290 nm. Mesa geometry devices of different active areas are fabricated and characterized for spectral responsitivity, speed, and noise performance. The responsivity of the devices near the cutoff wavelength is 0.07 A/W. The detector...

We report on low-frequency noise characteristics of visible-blind GaN p-n junction photodetectors. Carrier hopping through defect states in the space charge region, believed to be associated with dislocations, is identified as the main mechanism responsible for the dark conductivity of the photodiodes. Under reverse bias, the dark current noise has...

We report novel GaN detectors grown by molecular beam epitaxy on Si(111) substrates. Wurtzite structure epitaxial GaN exhibits room-temperature photoluminescence with a band-edge-related emission width as narrow as 7 nm and intensities comparable to high quality layers grown on sapphire by metalorganic chemical vapor deposition. Spectral response o...

Carrier lifetime measurements are an indispensable tool in semiconductor laser characterization. They allow determination of recombination rates, threshold current density, and other important device parameters. Experimental results on differential carrier lifetimes of gain-guided, proton-implanted and index-guided, oxide-defined vertical-cavity, s...

We report on the fabrication and characterization of p-π-n GaN ultraviolet detectors. The peak responsivity at ∼363   nm is measured to be 0.1 A/W in the photovoltaic mode, and 0.14 A/W with a bias of -15 V. Speed measurements have shown the photoresponse to be RC-limited with the response time decreasing from 17.4 ns at zero bias to 10.3 ns at -6...

We report on the measurements of static and dynamic polarization properties of vertical-cavity surface-emitting lasers (VCSELs) placed in a T-shaped external cavity. Internal losses and quantum efficiency are measured independently for the two polarization directions. The material gain is found to be isotropic. Dynamic stability of the polarization...

We report on the fabrication and characterization of vertical geometry transparent Schottky barrier ultraviolet detectors based on n−/n+-GaN structures grown over sapphire substrates. Spectral responsivity measurements were made using illumination through the UV transparent Schottky barrier metal. A responsitivity as high as 0.18 A/W was measured f...

We report on measurements of the spontaneous emission factor for oxide-confined InGaAs vertical cavity surface emitting lasers. The spontaneous emission factor is determined as a function of the active layer volume from the measurement of small-signal harmonic distortion at threshold. For a 3×3 μm oxide aperture device we obtain spontaneous emissio...

We describe dynamic properties of rectangular etched post vertical-cavity surface-emitting lasers designed for increased polarization stability. These lasers show polarization extinction ratios higher than 20 dB in CW and under high-speed large signal modulation. The high degree of polarization stability allows for error-free transmission in polari...

The consequences of polarization instability on the performance of polarization sensitive free-space optical links based on vertical-cavity surface-emitting lasers are evaluated experimentally. We show that the signal-to-noise ratio decreases to unacceptably low values when the bit rate of the link exceeds 300 Mb/s, resulting in bit error rate floo...

In the work presented here we study polarization-related dynamic and noise properties of vertical-cavity surface-emitting lasers (VCSELs) and analyze their performance in polarization-selective free-space optical data transmission links.

We show here that the polarization instability results in signal-to-noise ratio (SNR) degradation and the appearance of bit error-rate (BER) floors in polarization-sensitive optical links. This limits performance of vertical cavity surface emitting laser [VCSEL-based] free-space optical interconnects to data rates significantly lower than the laser...

We observe a polarization instability in circularly symmetric vertical‐cavity surface‐emitting lasers. A relatively long time, 3–5 ns, is required to establish a dominant polarization state. Under high‐speed digital modulation this leads to strong enhancement, 20–30 dB, in polarization resolved low‐frequency relative intensity noise. This polarizat...

We present, for the first time, a study of polarization instability induced RIN (relative intensity noise) enhancement in VCSELs. Devices under study are nominally single-mode top-emitting GaAs/AlGaAs VCSELs with an operating wavelength of 850 nm. Current confinement and gain guiding are obtained by double proton implantation. Detailed results of b...

We describe measurements of dynamic wavelength shift in single mode vertical cavity surface emitting lasers operating at 850 nm. Small signal modulation experiments yield a linewidth enhancement factor 3.7<α<4.5, depending on the modulation frequency. Under large signal modulation we measure Δν×Δτ∼3.6 for gain switched pulses. The dependence of dyn...

A combination of spontaneous emission lifetime and spectral measurements is used to estimate the threshold carrier density in small diameter gain guided vertical cavity surface emitting lasers. Differential spontaneous emission lifetimes measured below threshold are extrapolated to a τth=0.4 ns at threshold. The corresponding threshold carrier dens...

A new experimental technique for the measurement of intrinsic parameters of vertical cavity surface emitting lasers is suggested. Using an external cavity with variable reflectivity we measure the internal quantum efficiency of ηi=0.6 and internal losses of αi=10 cm−1 in a gain guided AlGaAs/GaAs laser operating at 850 nm. In addition, transparency...

The process of pumping current-controlled switching between two orthogonally polarised modes is studied. The switching is shown to occur between the modes of different types (DFB-like and Fabry-Perot-like), separated by a spectral interval as wide as about 240 Å

Measurements of the α‐factor, the linewidth‐power product, and the differential gain in AlGaAs/GaAs vertical cavity surface emitting lasers are presented. The linewidth power product of 95 MHz mW which results in the α‐factor of 3.7 is obtained. The α‐factor as a ratio of the refractive index and gain derivatives with respect to the carrier density...

Summary form only given. We report obtaining optical pulses 0.64 ps wide at a 104 GHz repetition rate from a passively mode-locked InGaAsP/InP laser diode. The laser emission spectrum corresponds to the amplification band of erbium-doped fiber amplifiers

Subpicosecond optical pulses are generated by passive modelocking in bulk active layer InGaAsP semiconductor lasers under CW pumping. The saturable absorber regions are formed by deep implantation of heavy ions into the diode facets. Optical pulses with 0.64 ps width are realised at 110 GHz repetition rate without using any external AC sources. No...

Recent progress in laser diodes with an ion-implanted fast saturable absorber resulted in generation of ultrashort optical pulses both in the gain-switching and in the passive mode-locking regimes. ¹⁻³ Normally, an implanted laser generates low intensity non-transform-limited pulses or pulse trains. Application of a fiber amplifier to increase the...

Not Available

1.7 ps solitons were obtained by 30 dB amplification of a signal from a laser diode with a fast saturable absorber and a two-cascade erbium-doped fibre amplifier.

The combination of a picosecond laser diode, operating within the 1550nm wavelength region and an erbium-doped fibre amplifier, is an attractive proposition since it allows one to realise a miniature source of ultra-short pulses.

The achievement of single-frequency lasing in an InGaAsSb/GaSb injection laser with distributed feedback is reported. Single-frequency lasing spectra under pulsed pumping are presented. The refractive index of the active material (InGaAsSb) at a lasing wavelength of 1.78 micron was determined on the basis of data on Bragg-lasing under optical and i...

A study was made of stimulated emission from mesa-stripe distributed-feedback lasers in the form of double heterostructures with separate electron and optical confinement. A diffraction grating with a period Λ = 0.46 μm, formed on the surface of the upper waveguide layer by holographic lithography, ensured distributed feedback in the second order....

Low-threshold distributed feedback lasers have been produced on the basis of InGaAsP/InP double heterostructures. Wide-contact lasers based on this structure have a current density threshold of 2-3 kA/sq cm and coupling coefficients in the range 130-140 per cm. In the continuous-wave mode, the maximum output power of the lasers does not exceed 3 mW...

The emission characteristics of InGaASP/InP injection lasers with a quantum-well active layer (300 A thick) are investigated experimentally using pumping pulses of different duration. It is found that the emission dynamics of heterolasers with an active layer produced by liquid epitaxy has certain characteristics that distiguish these lasers from h...