Laser Diode Pumped Unidirectional Ring Laser Resonator with AOM Q-switch

ＬａｓｅｒＤｉｏｄｅＰｕｍｐｅｄＵｎｉｄｉｒｅｃｔｉｏｎａｌＲｉｎｇＬａｓｅｒＲｅｓｏｎａｔｏｒｗｉｔｈＡＯＭＱ┐ｓｗｉｔｃｈＪ．Ｃｈｅｎ１）Ａ．Ｄｅｈｎ２）Ｈ．Ｊ．Ｅｉｃｈｌｅｒ２）Ａ．Ｈａａｓｅ２）Ｏ．Ｍｅｈｌ２）（１）ＮａｔｉｏｎａｌＫｅｙＬ...     

A Copper Laser with Flowing Ne-HBr Buffer Gas

ＡＣｏｐｐｅｒＬａｓｅｒｗｉｔｈＦｌｏｗｉｎｇＮｅ－ＨＢｒＢｕｆｆｅｒＧａｓ￥ＪＩＹｉｎｇ；ＬＩＡＮＧＰｅｉｈｕｉ；ＳＨＥＮＱｉｍｉｎ；ＺＨＡＮＧＧｕｉｙａｎ；ＬＩＮＦｕｃｈｅｎｇ（ＳｈａｎｇｈａｉＩｎｓｔｉｔｕｔｅｏｆＯｐｔｉｃｓａｎｄＦｉｎｅＭｅ...     

A Novel Tunable Dual-frequency Laser with Large Frequency Difference

1　ＩｎｔｒｏｄｕｃｔｉｏｎＢｉｒｅｆｒｉｎｇｅｎｔｄｕａｌ ｆｒｅｑｕｅｎｃｙｌａｓｅｒ[1] ｉｓｂａｓｅｄｏｎｍｏｄｅ ｓｐｌｉｔｔｉｎｇｔｅｃｈｎｏｌｏｇｙ[2 ] ａｎｄａｂｉｒｅｆｒｉｎｇｅｎｔｅｌｅｍｅｎｔｉｓｉｎｓｅｒｔｅｄｉｎｔｈｅｒｅｓｏｎａｎｔｃａｖｉｔｙｏｆｔｈｅｌａｓｅｒｔｏ ｐｒｏｄｕｃｅｄｉｆｆｅｒｅｎｔｆｒｅｑｕｅｎｃｉｅｓ.Ｔｈｅｆｒｅｑｕｅｎｃｙｄｉｆｆｅｒｅｎｃｅｃａｎｂｅｔｕｎｅｄｂｙｃｈａｎｇｉｎｇｔｈｅｏｐｔｉｃａｌｃｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆｔｈｅｉｎｔｒａ…     

Pulse–Periodic Diffuse Discharge with Self-Ionization in a Gas Flow

Technical Physics - A pulse–periodic diffuse discharge self-initiated in an atmospheric-pressure air flow passing through an annular gap with a strongly nonuniform electric field has been...     

Gas‐Kinetic Temperature of Planar High‐Frequency Capacitive Discharge Plasma in N2/CO2/He Gas Mixtures

Using methods of emission spectroscopy, we have determined the gaskinetic temperature fields of planar highfrequency capacitive discharge plasma in N₂/CO₂/He gas mixtures depending on the excitation frequency, discharge current, pressure, and chemical composition of the mixture. It is shown that the dominant contribution to the neutral component heating in the center of the discharge chamber is made by the processes of V–T relaxation of vibrationally excited molecules N₂(X ¹, V) and CO₂(X ¹, V), whereas in the zones near the electrodes an important role in the heating is played, along with the V–T relaxation of the N₂(X ¹, V) and CO₂(X ¹, V) molecules, by the processes of deactivation of the metastable states A ³ of the N₂ molecule.     

Synchronously Pumped Mode-Locked 1.89 μm Tm-Doped Fiber Laser with High Detuning Toleration

We propose and demonstrate a synchronously pumped mode-locked Tm-doped fiber(TDF) laser without any extra mode-locking elements. Pumped by a 1.56 μm pulse fiber laser, the TDF laser generates 1.17 ps pulses with a spectral width of 9.7 nm and a repetition rate of 9.33 MHz. The emission wavelength is tunable along with the cavity length detuning in a wide range of 3 mm. The high detuning toleration is beneficial to achieve high temperature and vibration stability in all-fiber configuration lasers.     

An Innovative Gas Sensor with On-Chip Reference Using Monolithic Twin Laser

An innovative gas sensor with on-chip reference using a monolithic twin laser is proposed. In this sensor a monolithic twin laser generates two closer laser beams with slight different wavelengths alternatively, one photodiode is used to catch both absorption and reference signals by time division multiplexing. The detection of nitrous oxide adopting this scheme using a 2.1μm antimonide laser and an InGaAs photodiode has been demonstrated experimentally with detection limit below 1ppm. Using this on chip reference scheme the fluctuations from the optical path and devices can be compensated effectively; the sensor system is simplified distinctly.     

Mutually Pumped Phase Conjugation of Three Incoherent Beams with a Novel Photorefractive Crystal

Ｍｕｔｕａｌｌｙ　Ｐｕｍｐｅｄ　Ｐｈａｓｅ　Ｃｏｎｊｕｇａｔｉｏｎ　ｏｆ　Ｔｈｒｅｅ　Ｉｎｃｏｈｅｒｅｎｔ　Ｂｅａｍｓ　ｗｉｔｈ　ａ　Ｎｏｖｅｌ　Ｐｈｏｔｏｒｅｆｒａｃｔｉｖｅ　ＣｒｙｓｔａｌＭｕｔｕａｌｌｙＰｕｍｐｅｄＰｈａｓｅＣｏｎｊｕｇａｔｉｏ...     

Combustion Dynamics of a Propane–Air Gas Mixture when It Is Ignited by a Streamer Microwave Discharge

Technical Physics - The results of experimental studies of combustion of propane–air gaseous mixture when it was ignited by a microwave discharge have been described. The mixture with...     

Broad Beam Gas Ion Source with Hollow Cathode Discharge and Four-grid Accelerator System

1 Introduction Ion sources with wide energy and current ranges are used extensively in industrial applications such as ion implantation, etching, and deposition. Broad beam ion sources with a uniform current distributions are needed for many industrial applications and development of commercial ion bean technologies for surface modification of materials is impossible without highly efficient, simple, and dependable ion sources. These and other needs have spurred the development of high efficiency ion sources that can produce ion beams with high energy and current and require low or no maintenance.     

Ti: sapphire Laser Pumped Yb: YAG Laser with Cr~(4 ): YAG as a Passive Q-switch

The Ti: sapphire laser pumped Yb: YAG passively- Q-switched laser with Cr~(4 ): YAG as asaturable absorber experiment was performed. The Mira 900 tunable Ti: sapphire laser with anoutput power up to 1 W was used as a pump source. The optical pump system was composed of aspherical lens (f = 75 mm) for focusing the pump beam to a circular spot with a diameter of about50 up, the pumping power was measured to be up to 920 mW. The laser cavity was configured tobe semispherical, and was formed…     

Diode Laser‐Excited Optogalvanic and Absorption Measurements of Uranium in a Hollow Cathode Discharge

Optogalvanic spectra for fifty two transition lines of uranium in the wavelength ranges of 662–683, 774–792, and 834–862 nm were measured by using external‐cavity diode lasers. Among these transitions, 860.795 nm and 682.691 nm were chosen for a detailed investigation of the detection limit for uranium by wavelength modulation spectroscopy due to its stronger signal magnitudes. A detection limit of about 2 × 10^? 5 absorbance achieved at 860.795 nm is more sensitive than that obtained at 682.691 nm, but the absorption spectrum at 682.691 nm is preferable to determine the isotope ratio due to the narrower hyperfine structure as well as the larger isotope shift. A preliminary result for an isotope ratio determination in a depleted sample is presented.     

A Continuous-Wave Ho：YA103 Laser with Output 8.5 W Pumped by a 1.91μm Laser at Room Temperature

A cw high efficient Ho：YAI03 laser pumped by 1.91 μm diode-pumped Tm：YLF laser at room temperature is realized. The maximum output power reaches 8.5 W when the incident pump power is 15.6 W. The slope efficiency is 63.7%, and the Tm：YLF to Ho：YAP optical conversion efficiency is 54.5%. The laser wavelength is 2118.3nm when the transmission of output coupler is 30%. The beam quality factor is M2 -1.39 measured by the traveling knife-edge method.     

Microwave Photonic Signal Down‐Conversion Using a Novel Two‐Frequency Bragg Grating Based Brillouin Fiber Laser

A simple technique using a novel twofrequency Bragg grating based Brillouin fiber laser to downconvert high frequency microwave photonic signals is presented. The mechanism of the Brillouin fiber laser and the principle of this technique for microwave photonic signal downconversion are analyzed. The 12GHz microwave photonic signals are experimentally downconverted to 1.13GHz IF signal with the technique.     

Erratum to: Combustion Dynamics of a Propane–Air Gas Mixture When it is Ignited by a Streamer Microwave Discharge

Technical Physics - erratum     

A Novel Multisection Distributed Feedback Laser with Varied Ridge Width for Self-Pulsation Generation

A novel ridge-waveguide multisection （MS） distributed feedback （DFB） laser, which consists of two identical DFB sections but different ridge widths, is proposed to generate beating-type self-pulsations （SPs）. The spatiotemporal dynamic response of such a multisection DFB laser is calculated based on a large-signal travelling-wave model. Self-pulsating output at about 150GHz is predicted, and evidences for the beating mechanism of the SPs are provided. To the best of our knowledge, this is the first report on SP generated by MS-DFB lasers with varied ridge width. Compared to other alternatives, such devices are much easier to implement and also enjoy the advantages of lower cost and higher design freedom.     

Two‐Wave CO2 Laser with Loss Modulation in Both Channels

The nonlinear dynamics of a twowave CO₂ laser with continuous pumping by an electric discharge and loss modulation in both channels is investigated theoretically. In modulation of losses with the same frequencies it is possible, by changing the shift of the phases of modulating signals, to monitor simply enough the amplitude, form, duration, and depth of modulation and also the repetition rate of radiation. Depending on the shift of phases, the maximum response can be concentrated in the lowfrequency region or propagate also to the region of high frequencies. If losses in both channels are modulated with different frequencies, a change in the relationship between these frequencies predominantly leads to a change in the shape, magnitude, and structure of response in the lowfrequency region of the amplitudefrequency characteristic (AFCh). In the highfrequency region of the amplitudefrequency characteristic, beginning from the peaks of the doubling of the vibration period, where inphase modes of radiation are implemented, the response virtually does not change. Similar regularities are observed on change in the shift of phases.     

A Continuous-Wave Ho:YAlO3 Laser with Output 8.5W Pumped by a 1.91μm Laser at Room Temperature

A cw high efficient Ho:YAlO₃ laser pumped by 1.91μm diode-pumped Tm:YLF laser at room temperature is realized. The maximum output power reaches 8.5W when the incident pump power is 15.6W. The slope efficiency is 63.7%, and the Tm:YLF to Ho:YAP optical conversion efficiency is 54.5%. The laser wavelength is 2118.3nm when the transmission of output coupler is 30%. The beam quality factor is M²~1.39 measured by the traveling knife-edge method.     

A 0．98μm Laser Diode Pumped Erbium－Doped Fiber Amplifier with 40nm Bandwidth

Ａ０．９８μｍＬａｓｅｒＤｉｏｄｅＰｕｍｐｅｄＥｒｂｉｕｍ－ＤｏｐｅｄＦｉｂｅｒＡｍｐｌｉｆｉｅｒｗｉｔｈ４０ｎｍＢａｎｄｗｉｄｔｈ￥ＬＩＪｉｎｇｈｕｉ；ＰＥＮＧＪｉａｎｇｄｅ；ＪＩＡＮＧＸｉｎ；ＹＡＯＭｉｎｙｕ；ＷＵＧｅｎｇｓｈｅｎｇ；ＦＡＮＣｈｏ...