Multibound soliton formation in an erbium-doped ring laser with a highly nonlinear resonator

We have studied the generation of low-noise ultrashort multibound solitons in the telecommunication spectral window in an erbium-doped all-fiber ring laser with a highly-nonlinear resonator mode-locked by a nonlinear polarization evolution effect. The multibound soliton generation is obtained with more than 20 bound dechirped pulses with a duration of 240 fs at a repetition rate of 11.3 MHz (with a signal-To-noise ratio of 73.3 dB), the relative intensity noise is <-140 dBc/Hz, and the Allan deviation of the repetition frequency does not exceed $\sim 1.3\cdot 10^{\mathbf {-8}}$ with a time averaging window of 100 s

Multibound solitons generation with a controllable number of bound states in a passive mode-locked all-fiber erbium-doped ring laser

We have studied generation of stable and low-noise de-chirped ultrashort solitons in bound states and we have experimentally demonstrated the formation multi-bound solitons with the controllable number of bound states 7 < N < 17 by pump power variation. A numerical simulation of the influence of various types of fluctuations on the generation mode was also carried out

Thermo-optical and lasing characteristics of Cr2+-doped CdSe single crystal as tunable coherent source in the mid-infrared

We report on a comprehensive characterization of Cr2+-doped CdSe single crystal as an efficient active material for tunable laser applications in the mid-infrared spectral region. Optical gain, thermo-optical behavior, power efficiency, scalability and wavelength tunability have been thoroughly investigated. Using an antireflection-coated crystal pumped by a Tmfiber laser at at 1.94 μm, 1-W CW output power and 50% slope efficiency at 2.65 μm emission wavelength have been obtained in a diffraction-limited output beam. An output peak power of 2.5 W has been achieved without significant beam distortion in a quasi-CW regime. Exploiting an intra-cavity diffraction grating in a Littrow configuration, a maximum tuning range of 900 nm from 2.22 to 3.12 μm, limited by the finite bandwidth of resonator components, has been demonstrated with an uncoated crystal

SCIENTIFIC AND EDUCATIONAL CENTERS: TO A NEW PARADIGM OF ENGINEERING EDUCATION

The article is devoted to the innovative system of the scientific and educational centers formed at Bauman Moscow state technical university, their contribution to training of graduates. It is shown that the system of the scientific and educational centers combining real production, scientific researches, business processes and modern educational technologies provides the necessary conditions and a special environment for training of specialists ready to participate in innovative development, and to shape the future of the Russian science and the industry

Femtosecond Er-Doped All-Fiber Laser with High-Density Well-Aligned Carbon-Nanotube-Based Thin-Film Saturable Absorber

We have studied the ultrafast saturation behavior of a high-density well-aligned single-walled carbon nanotubes saturable absorber (HDWA-SWCNT SA), obtained by a high-pressure and high-temperature treatment of commercially available single-wall carbon nanotubes (SWCNTs) and related it to femtosecond erbium-doped fiber laser performance. We have observed the polarization dependence of a nonlinear optical saturation, along with a low saturation energy level of &lt;1 fJ, limited to the detector threshold used, and the ultrafast response time of &lt;250 fs, while the modulation depth was approximately 12%. We have obtained the generation of ultrashort stretched pulses with a low mode-locking launching threshold of ~100 mW and an average output power of 12.5 mW in an erbium-doped ring laser with the hybrid mode-locking of a VDVA-SWNT SA in combination with the effects of nonlinear polarization evolution. Dechirped pulses with a duration of 180 fs were generated, with a repetition rate of about 42.22 MHz. The average output power standard deviation was about 0.06% RMS during 3 h of measurement

Properties of Scalable Chirped-Pulse Optical Comb in Erbium-Doped Ultrafast All-Fiber Ring Laser

We report on a scalable chirped-pulse Er-doped all-fiber laser, passively mode-locked by single-wall carbon nitride nanotubes. The average output power is ~15 mW, which corresponds to a peak power of ~77 W, and pulse energy of ~1.9 nJ and was achieved using a single amplification stage. We observed chirped-pulse generation with a duration of ~24.6 ps at a relatively low repetition rate of ~7.9 MHz, with a signal-to-noise ratio of ~69 dB. To characterize the short-term stability of the obtained regime, we have measured the relative intensity noise of the laser, which is &lt;−107 dBc/Hz in the range of 3 Hz–1000 kHz. It should be noted that the standard deviation of root mean square of average power does not exceed a magnitude of 0.9% for 3 h of measurement

Laser performance of Cr 2+ :CdSe crystal with anti-reflection coating

We demonstrated a continuous-wave laser using an anti-reflection coated Cr 2+ :CdSe crystal with transmission of 98 % at wavelength range from 2.0 to 2.7 μm and with relatively large laser damage threshold of 30 MW/cm 2 for the first time. A maximum output power of 1 W at wavelength 2450 nm with an optical-optical efficiency of 48 % and a slope efficiency of 50 % was obtained when the incident pump power was 2.1 W