Wlodzimierz Strupinski

Chirped pulse amplification of a femtosecond Er-doped fiber laser mode-locked by a graphene saturable absorber

In this work we demonstrate for the first time, to our knowledge, a chirped pulse amplification (CPA) setup utilizing a graphene mode-locked femtosecond fiber laser as a seed source. The system consists of a mode-locked Er-fiber oscillator operating at 1560?nm wavelength, a grating-based pulse stretcher, two-stage amplifier and a grating compressor. The presented setup allows the amplification of the seed up to 1?W of average power (1000 times amplification) with linearly polarized 810 fs pulses and 20?nJ pulse energy at a 55?MHz repetition rate. The whole design is based on single-mode fibers, which allows one to maintain excellent beam quality, with M2 less than 1.17.

Er-Doped Fiber Laser Mode-Locked by CVD-Graphene Saturable Absorber

Erbium-doped fiber laser passively mode-locked by bilayer graphene is presented. The graphene layers were grown by chemical vapor deposition (CVD) on Cu substrate and transferred onto a fused silica window, forming a saturable absorber (SA). Low non-saturable losses and modulation depth as high as 55% allowed to achieve soliton pulses with over 11 nm bandwidth and nearly-transform limited 315 fs duration at 1564 nm center wavelength. The paper describes the design of the laser construction, as well as the graphene-SA preparation process. Our study demonstrates, that CVD-Cu graphene transferred on glass substrate may be used for efficient mode-locking of fiber lasers.

Graphene and carbon nanocompounds: biofunctionalization and applications in tissue engineering

In tissue engineering, the possibility of a comprehensive restoration of the tissue, structure or a portion of the organ is largely determined by the type of material used. A wide range of materials such as graphene and other carbon nanocompounds which have different physical and chemical properties can be expected to react differently upon contact with biomolecules, cells and tissues. This mini-review describes the current knowledge on biocompatibility of graphene and its derivatives with a variety of mammalian cells, such as osteoblasts, neuroendocrine cells, fibroblasts NIH/3T3 line, PMEFs (primary mouse embryonic fibroblasts), stem cells and neurons. The results from different studies give hope for the possibility of graphene to be used in the regeneration of almost all tissues, including neural tissue implants or in the form of neural chips, which may allow in the future treatment of degenerative diseases and injuries of the central nervous system.

Role of structure of C-terminated 4 H -SiC( 000 1 ¯ ) surface in growth of graphene layers: Transmission electron microscopy and density functional theory studies

The principal structural defects in graphene layers, synthesized on a carbon-terminated face, i.e., the SiC(000

Graphene oxide overprints for flexible and transparent electronics

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Nitrogen doping of chemical vapor deposition grown graphene on 4H-SiC (0001)

) face of a

Insights into electrocatalytic activity of epitaxial graphene on SiC from cyclic voltammetry and ac impedance spectroscopy

4H

Biocompatibility of pristine graphene monolayer: Scaffold for fibroblasts

-SiC substrate, are investigated using microscopic methods. Results of high-resolution transmission electron microscopy (HRTEM) reveal their atomic arrangement. The mechanism of such defects creation, directly related to the underlying crystallographic structure of the SiC substrate, is proposed. The connection between the

The study of the interactions between graphene and Ge(001)/Si(001)

4H

CVD-Graphene-Based Flexible, Thermoelectrochromic Sensor

-SiC(000