Showing papers on "Ring laser published in 1991"
TL;DR: An amplifying nonlinear-optical fiber loop mirror is used as the gain element in an all-fiber ring laser, and the resulting double-loop structure resembles a figure eight.
Abstract: An amplifying nonlinear-optical fiber loop mirror is used as the gain element in an all-fiber ring laser. The resulting double-loop structure resembles a figure eight. The output of the amplifying nonlinear-optical fiber loop mirror is fed back to the input through an optical isolator to ensure unidirectional operation. The laser produces 2-ps transform-limited pulses. The pulse energy corresponds to that of the fundamental soliton in the fiber used.
367 citations
TL;DR: A stimulated Brillouin fiber ring laser with a spectral width of 2 kHz and an intrinsic linewidth of less than 30 Hz has been demonstrated, and applications of such a laser include laser linewsidth narrowing, microwave frequency generation, high-rate amplitude modulation, and optical inertial rotation sensing.
Abstract: A stimulated Brillouin fiber ring laser with a spectral width of 2 kHz and an intrinsic linewidth of less than 30 Hz has been demonstrated. Applications of such a laser include laser linewidth narrowing, microwave frequency generation, high-rate amplitude modulation, and optical inertial rotation sensing.
335 citations
TL;DR: In this paper, a self-starting, passively mode-locked erbium fiber laser is proposed based on the reflection properties of a nonlinear amplifying loop mirror and provides a stable source of picosecond pulses.
Abstract: A novel self-starting, passively mode-locked erbium fibre laser is reported The scheme is based on the reflection properties of a nonlinear amplifying loop mirror and provides a stable source of picosecond pulses
178 citations
TL;DR: In this paper, the authors show that superluminous Stokes pulses of quasisoliton type and partial self-induced transparency for the pump can be obtained even with a cw-coupled pump wave.
Abstract: Nonstationary stimulated Brillouin backscattering in a large gain optical-fiber ring cavity laser exhibits superluminous Stokes pulses of quasisoliton type and partial self-induced transparency for the pump. Experimental evidences, comforted by numerical simulation of the three-wave coherent model taking the acoustic-wave dynamics into account, show that this class of long transients occurs even with a cw-coupled pump wave.
94 citations
TL;DR: In this paper, a simple interferometric technique was used to identify phase singularities in a continuous single longitudinal mode Na2 ring laser, which can be used to elucidate the structure of higher order stationary patterns.
Abstract: We report the use of a simple interferometric technique which allows direct identification of phase singularities in laser fields. Phase singularities are observed in families of optical patterns formed via cooperative frequency mode locking in a continuous single longitudinal mode Na2 ring laser. The interferometric technique complements a previously reported astigmatic imaging method, and is superior in that it can be used to elucidate the structure of the higher order stationary patterns.
77 citations
TL;DR: Measurements on a passively mode-locked dye laser demonstrate a sensitive gyro-type response, when Fresnel drag in air is used to simulate rotation, which is unexpected for a homogeneously broadened ring laser.
Abstract: Measurements on a passively mode-locked dye laser demonstrate a sensitive gyro-type response, when Fresnel drag in air is used to simulate rotation. Such a response is unexpected for a homogeneously broadened ring laser.
73 citations
TL;DR: In this article, an all fiber, diode-pumped, electrically tunable ring laser is reported. Gain is provided by an erbium-doped fiber and tuning by a fibre Fabry-Perot etalon.
Abstract: An all fibre, diode-pumped, electrically tunable ring laser is reported. Gain is provided by an erbium-doped fibre and tuning by a fibre Fabry-Perot etalon. The threshold at l.566 μm is 2.9mW, the slope efficiency is 0.15 and the output power is 4.2 mW with 32 mW of pump power. The output wavelength can be tuned from 1.525 to 1.586 μm with a variation in power of less than 3.5 dB.
68 citations
TL;DR: In this article, an actively mode-locked erbium-doped ring laser with birefringent polarisation-maintaining fiber was used to produce dual pulses with different peak wavelengths and durations as short as 2ps.
Abstract: Dual pulses each with different peak wavelengths and durations as short as 2ps were concurrently produced with an actively mode-locked erbium-doped fibre ring laser made in part with birefringent polarisation-maintaining fibre. Peak wavelength separations measured in the experiment agreed well with the theoretical values.
66 citations
TL;DR: A cw Ti:A1(2)O(3) ring laser with a threshold power of 119 mW is demonstrated, which provides a tunable source of single-frequency, diffraction-limited radiation that is suitable for injection seeding.
Abstract: A CW Ti:Al2O3 ring laser with a threshold power of 119 mW is demonstrated. It provides a tunable source of single-frequency, diffraction-limited radiation that is suitable for injection seeding. The Ti:Al2O3 laser is operated with a diode-laser-pumped, frequency-doubled, Nd:YAG laser as the sole pump source.
59 citations
TL;DR: In this article, a diode-pumped, broadly tunable, single frequency erbium-doped fiber ring laser is reported, which can be tuned to wavelengths between 1.530 and 1.575 μm and operates singlemode throughout this range.
Abstract: A diode-pumped, broadly tunable, single frequency erbium-doped fibre ring laser is reported. Tuning and single longitudinal mode selection are accomplished by use of two fibre Fabry-Perot etalons. The threshold for 1.48 μm pumping is 8.8 mW and the slope efficiency is 11.5%. The laser can be tuned to wavelengths between 1.530 and 1.575 μm and operates singlemode throughout this range. Its linewidth is measured at 1.56 μm to be less than 5.5 kHz.
58 citations
TL;DR: By second-harmonic generation the amplification of a continuous-wave single-mode ring dye laser in Ti:sapphire was presented and high-peak-power UV pulses from the amplified single- mode laser were obtained.
Abstract: We present the amplification of a continuous-wave single-mode ring dye laser in Ti:sapphire. A peak gain of 2 × 106 has been obtained in a passive multipass amplifier, which yielded 20-nsec pulses of 0.7-mJ energy at 780 nm. We discuss the advantages of this passive multipass amplifier in comparison with a regenerative amplifier that we have also developed. By second-harmonic generation we obtained high-peak-power UV pulses from the amplified single-mode laser.
TL;DR: Injection seeding of a pulsed, laser-pumped, titanium-doped-sapphire ring laser by both continuous-wave dye and diode lasers is demonstrated and the spatial and longitudinal mode-matching requirements for successful seeding are discussed.
Abstract: We demonstrate injection seeding of a pulsed, laser-pumped, titanium-doped-sapphire ring laser by both continuous-wave dye and diode lasers. As little as 100 μW of seed light is required to produce 4 mJ of 30-nsec TEM00 output having a bandwidth of less than 25 MHz FWHM. Using an atomic resonance filter we find that more than 99.9% of the energy is at the 780-nm seed wavelength. We discuss the spatial and longitudinal mode-matching requirements for successful seeding.
TL;DR: In this article, a simple technique using a scanning confocal Fabry-Perot etalon and a stabilized helium-neon laser is described that can be used to correct the long-term drift in output frequency of actively stabilized commercial dye lasers.
Abstract: A simple technique using a scanning confocal Fabry‐Perot etalon and a stabilized helium‐neon laser is described that can be used to correct the long‐term drift in output frequency of actively stabilized commercial dye lasers. Using this technique the long‐term drift in the ultraviolet output frequency of an intracavity‐doubled Coherent Inc. CR699‐21 ring dye laser has been reduced to ≲±2 MHz.
TL;DR: In this paper, an erbium doped fiber ring laser with singlemode operation over a continuous wavelength tuning range of 44 nm (1528nm-1572nm) with laser linewidths of less than 10 kHz is reported.
Abstract: An erbium doped fibre ring laser enabling singlemode operation over a continuous wavelength tuning range of 44 nm (1528nm–1572nm) with laser linewidths of less than 10kHz is reported.
TL;DR: A diode-laser-pumped Nd:YAG ring laser incorporating a rhomb-shaped acousto-optic modulator as its only optical component is reported in this article.
TL;DR: A 0.91-W single-frequency diode-pumped Nd:YAG laser at 1.06 microm is demonstrated with a TEM(00) output and a 60% slope efficiency from another nonplanar monolithic ring laser with diffraction-limited, single- frequencies output is reported.
Abstract: A 0.91-W single-frequency diode-pumped Nd: YAG laser at 1.06 μm is demonstrated with a TEM00 output. We also report a 60% slope efficiency from another nonplanar monolithic ring laser with diffraction-limited, single-frequency, 1.06-μm output. Injection locking of two 0.17-W monolithic nonplanar ring resonators gave 0.34 W of single-mode power. Actively controlled injection locking of two lasers was demonstrated for indefinite periods.
Patent•
20 Feb 1991
TL;DR: In this paper, a tunable optical filter provides simultaneous tuning filtering between fibres (5 and 6 and 7 and 8) located within a capillary tube and mounted on a solenoid movable support.
Abstract: A tunable optical filter comprises an array (3) of optical fibre (5 to 8) located within a capillary tube (10) and mounted on a solenoid movable support (14) and positioned in front of a lens (4) and diffraction grating (2). The filter provides simultaneous tuning filtering between fibres (5 and 6 and 7 and 8). By coupling fibres (5 and 6) to a ring laser and fibre (8) to an optical receiv-er simultaneous tuning of a laser and receiver is possible. The filter finds particular application in passive optical networks.
TL;DR: In this article, a continuously tunable, cw 1.2-2.2 μm light by the difference mixing of a cw Nd: YAG lase from a Cw ring laser in temperature phase matched LiNbO3 is described.
TL;DR: In this article, a diode-pumped Nd:YLF ring laser is described which incorporates an acousto-optic rhomb to enforce unidirectional single frequency operation and Q-switching.
Patent•
28 Jun 1991TL;DR: In this article, a ring laser gyro is used to minimize the effects of lock-in and backscatter in a lasing cavity with a mode-locked laser, where the position of the stimulated counter rotating laser beams is controlled by two methods: wave propagation delay line and acousto-optic modulator shutter.
Abstract: A ring laser gyro that minimizes and avoids the effects of lock-in and backscatter. A ring laser is pumped in a lasing cavity with a mode-locked laser. Dual counterrotating pumped pulses are precisely positioned to avoid overlay in optical elements that contribute to lock-in and backscatter. The position of the stimulated counter rotating laser beams is controlled by two methods. In the first method the pumped pulses are synchronized with a wave propagation delay line. In the second method the pumped pulses are chopped by an acousto-optic modulator shutter to precisely time the location of the pumped pulses. Both methods are can be combined to achieve a hybrid synchronized and acousto-optic modulated approach.
TL;DR: In this article, a solid-state ring-laser gyroscope was demonstrated using a pair of semiconductor diodes in an external ring cavity, and the use of homogeneously broadened gain media was made possible by actively mode locking the laser.
Abstract: We have demonstrated a novel solid-state ring-laser gyroscope, which utilizes as the gain media a pair of semiconductor diodes in an external ring cavity. The use of homogeneously broadened gain media is made possible by actively mode locking the laser. We observe no evidence of frequency locking between the counterpropagating optical pulse trains generated in the cavity to within the limit of our experimental resolution.
TL;DR: Single-frequency Q-switched operation of a diode-laser-pumped Nd:YAG ring laser has been achieved by using an acousto-optic modulator both to enforce unidirectional operation and to provide Q switching.
Abstract: Single-frequency Q-switched operation of a diode-laser-pumped Nd:YAG ring laser has been achieved by using an acousto-optic modulator both to enforce unidirectional operation and to provide Q switching. Pulses with energies of 13 μJ and 36-ns duration have been obtained, corresponding to a peak power of 400 W, at a repetition rate of 1 kHz.
TL;DR: In this paper, a simple model was developed to describe polarization self-modulation in a ring laser cavity with a traveling-wave semiconductor laser amplifier as the gain medium and a set of difference-differential equations was derived and numerically solved.
Abstract: Numerical simulations performed show that polarization self-modulation in suitably designed semiconductor lasers into the tens of GHz frequency region should be possible. The calculations are based on a simple model developed to describe polarization self-modulation in a ring laser cavity with a traveling-wave semiconductor laser amplifier as the gain medium. A set of difference-differential equations is derived and numerically solved. Periodic oscillations in the two polarization modes are obtained as previously reported experimentally. An examination of the various parameters and their roles in maintaining this instability is also conducted. The results indicate that, in an appropriately designed semiconductor laser with a monolithically integrated intracavity TE-TM mode converter, ultrahigh frequency polarization self-modulation to at least 50 GHz should be possible. >
TL;DR: In this paper, a single mode LNA ring laser is described, which emits 60 mW at 1.083m. Thanks to a high frequency F-M- saturated absorption technique, this laser is directly locked to an atomic line in a ~He discharge cell.
Abstract: We describe a single mode LNA ring laser, which emits 60 mW at 1.083 ~m. Thanks to a high frequency F-M- saturated absorption technique, this laser is directly locked to an atomic line in a ~He discharge cell. The residual frequency jitter is 130kHz. We then present two examples of laser manipulation of helium 4 atoms in the 2~Sj metastable state, using this laser a density increase of the atomic beam by a factor of 8, with one-dimensional optical molasses, and a selective deflection of the metastable helium beam using a laser beam with curved wavefronts.
Patent•
24 May 1991
TL;DR: In this paper, a triangular ring laser gyroscope with a single anode, single cathode, and self-compensating discharge path is presented, which cancels gyro bias, bias drift, and noise.
Abstract: A triangular ring laser gyroscope having a single anode, single cathode, and self-compensating discharge path which cancels gyro bias, bias drift, and noise. The discharge path extends from the anode through a cross channel in the center of the gyro block to the cathode. Counter-propagating laser beams traverse one segment of the discharge path in the direction of the Langmuir flow from anode to cathode, and another segment of the discharge path of equal length in a direction opposite to that flow. The Langmuir return flow from cathode to anode occurs along the walls of the gyro cavity, producing a more uniform gas flow velocity in the central region of the discharge path. Drag effects on the counter-propagating laser beams are equal but opposite, and the laser beams traverse a more uniform region of the Langmuir flow when thermally-induced changes in the gyro cause beam wandering. Gyro bias, bias drift, and noise are substantially cancelled.
TL;DR: This work demonstrates, for the first time to their knowledge, a discretely tunable all-fiber frequency shifter based on mixing the outputs of two stimulated Brillouin scattering fiber ring resonator lasers.
Abstract: We demonstrate, for the first time to our knowledge, a discretely tunable all-fiber frequency shifter based on mixing the outputs of two stimulated Brillouin scattering fiber ring resonator lasers. The frequency tuning was achieved by differentially heating the rings. The observed temperature dependence of the frequency shift was as expected, with the discrete frequency jumps being equal to the free spectral range of the resonator.
TL;DR: A colliding-pulsemode-locked dye ring laser was mounted on a rotary stage and the beat frequency of the two output pulse trains was measured as a function of the rotation rate.
Abstract: A colliding-pulse-mode-locked dye ring laser was mounted on a rotary stage and the beat frequency of the two output pulse trains was measured as a function of the rotation rate. The measurements are in good agreement with the Sagnac theory.
TL;DR: In this paper, it was shown that the degeneracy of the clockwise and counterclockwise traveling waves in a ring laser can be eliminated by linearly coupling the two waves by means of backscattering, which leads to a frequency splitting of the normal modes.
Abstract: The degeneracy of the clockwise- and counterclockwise-traveling waves in a ring laser can be eliminated by linearly coupling the two waves by means of backscattering, which leads to a frequency splitting of the normal modes. In a theoretical treatment of this effect we stress the use of a standing-wave representation. We present, in particular, numerical results for the case in which the linear coupling is not much larger than the nonlinear coupling associated with gain saturation. We report experimental evidence of frequency splitting by analyzing the optical spectrum of a bidirectional ring dye laser with backscattering. The experimental results are in good agreement with the theoretical predictions.
Patent•
11 Jan 1991
TL;DR: In this article, a ring laser gyro has four legs and four corner mirrors, and one of the corner mirrors is partially transmissive, and the transmitted beam is sensed and converted into a digital signal.
Abstract: A ring laser gyro having a ring laser that preferably has four legs and four corner mirrors. At least one of the corner mirror is partly transmissive, and the transmitted beam is sensed and converted into a digital signal. The digital signal is fed back in two computer loops to at least one digital-to-analog converter, and thence to a transducer which drives at least one corner mirror inward and outward. One of the computer loops includes a stepped demodulator having four steps per cycle. The steps have voltages at the operating voltage of the transducer, that voltage plus an increment, the operating voltage, and that voltage less a decrement. The first loop sends an operating voltage to the digital-to-analog converters. The second loop demodulates the beam signal at a second harmonic of the demodulation of the first loop to produce a voltage signal which controls the amplitude of dithering of the movable mirrors. A stepped modulator, in synchronism with the demodulator of the first loop, delivers a modulation signal to the digital-to-analog converters to step the movable mirrors. The operating voltage moves the mirrors into a position wherein the laser cavity operates at its intensity mode peaks.
TL;DR: In this article, two totally and one partially reflecting V-shaped ring laser (trilaser) are combined in a unibodied structure to realize a triangular-shaped trilaser, which is made of three sections which meet at three facets.
Abstract: Total and partial reflection are demonstrated at the bends of V‐shaped lasers. By varying the angle of incidence to the facet at the bend, the reflectivity at this facet can be changed. Two totally and one partially reflecting V‐shaped lasers are combined in a unibodied structure to realize a triangular‐shaped ring laser (trilaser). Trilasers are made of three sections which meet at three facets. Two of the facets provide total internal reflection while the third allows partial transmission from which light output is obtained. The Q of the resultant planar cavity is modified by geometry, without the need for facet coating. V‐shaped lasers and trilasers are formed by using the chemically assisted ion beam etching technique in an AlGaAs/GaAs‐based single quantum well graded‐index separate confinement heterostructure material.