Vector rogue waves in a carbon nanotube mode-locked fiber laser

Summary form only given. Mechanisms of rogue waves (RWs) emergence have been extensively studied in fiber lasers with nonlinearly driven cavities [1], Raman fiber amplifiers and lasers [2], and fiber lasers via modulation of the pump [3]. Previously, it has been found that RWs can be emerged because of soliton-soliton interaction through the overlapping of their tails or soliton-dispersive wave interaction. The result of these interactions is a coupling enhancement that leads to chaotic pulse bunching in the form of soliton rain at the time scale of a round-trip time in a high pump power (800 mW) [4]. Such interaction can be controlled by the pump power modulation or/and by injecting a weak seeding signal and noise. Here, we report for the first time the observation of the soliton rain and soliton-soliton interaction that leads to the optical rogue wave emergence in a carbon nano-tube saturable absorber mode-locked fiber laser at low pump power (140mW) without pump modulation or injecting a weak signal and noise to the laser cavity. As we shown recently [5] that by tuning the interaction of two orthogonal-states of polarization (SOP) of the in-cavity birefringent and also the pump SOP whereas the polarization instability leading to the emergence of different optical RW events

Bound state vector solitons with locked and precessing states of polarization

We report experimental observation of new tightly and loosely bound state vector solitons with locked and precessing states of polarization in a carbon nanotube mode locked fiber laser in the anomalous dispersion regime

Exciton energy transfer in nanotube bundles

Photoluminescence is commonly used to identify the electronic structure of individual nanotubes. But, nanotubes naturally occur in bundles. Thus, we investigate photoluminescence of nanotube bundles. We show that their complex spectra are simply explained by exciton energy transfer between adjacent tubes, whereby excitation of large gap tubes induces emission from smaller gap ones via Forster interaction between excitons. The consequent relaxation rate is faster than non-radiative recombination, leading to enhanced photoluminescence of acceptor tubes. This fingerprints bundles with different compositions and opens opportunities to optimize them for opto-electronics.Comment: 5 pages, 5 figure

Isolator-free switchable uni- and bidirectional hybrid mode-locked erbium-doped fiber laser

An Erbium-doped fibre ring laser hybrid mode-locked with single-wall carbon nanotubes (SWNT) and nonlinear polarisation evolution (NPE) without an optical isolator has been investigated for various cavity conditions. Precise control of the state of polarisation (SOP) in the cavity ensures different losses for counter-propagating optical fields. As the result, the laser operates in quasi-unidirectional regime in both clockwise (CW) and counter-clockwise (CCW) directions with the emission strengths difference of the directions of 22 dB. Furthermore, by adjusting the net birefringence in the cavity, the laser can operate in a bidirectional generation. In this case, a laser pumped with 75 mW power at 980 nm generates almost identical 790 and 570 fs soliton pulses with an average power of 1.17 and 1.11 mW. The operation stability and pulse quality of the soliton pulses in both unidirectional regimes are highly competitive with those generated in conventional ring fibre lasers with isolator in the cavity. Demonstrated bidirectional laser operation can find vital applications in gyroscopes or precision rotation sensing technologies

Vector solitons in harmonic mode-locked erbium-doped fiber lasers

We report experimental study of vector solitons for the fundamental and harmonic mode-locked operation in erbiumdoper fiber lasers with carbon nanotubes based saturable absorbers and anomalous dispersion cavities. We measure evolution of the output pulses polarization and demonstrate vector solitons with various polarization attractors, including locked polarization, periodic polarization switching, and polarization precession

Poor fluorinated graphene sheets carboxymethylcellulose polymer composite mode locker for erbium doped fiber laser

We report poor fluorinated graphene sheets produced by thermal exfoliation embedding in carboxymethylcellulose polymer composite (GCMC) as an efficient mode locker for erbium doped fiber laser. Two GCMC mode lockers with different concentration have been fabricated. The GCMC based mode locked fiber laser shows stable soliton output pulse shaping with repetition rate of 28.5MHz and output power of 5.5 mW was achieved with the high concentration GCMC, while a slightly higher output power of 6.9 mW was obtained using the low concentration GCMC mode locker

Non-muscle invasive Bladder Cancer. Intravesical chemotherapy and BCG

Treatment of bladder cancer remains a challenge which should take a comprehensive approach that includes removal of the tumor, preventing recurrence of tumor, dispensary observation. Intravesical therapy is used in the treatment of superficial transitional cell bladder cancer (Та, T1 and carcinoma in situ) in order to treat existing or residual tumor, relapse prevention, prevention of disease progression and prolongation of life for patients. The primary stage of the disease and the degree of differentiation of the tumor were important determinants of prognosis, regardless of treatment. Intravesical chemotherapy reduces the recurrence of tumors by 22% of. At present, BCG immunotherapy remains the most effective treatment and prevention of transitional cell bladder cancer (Та, T1, carcinoma in situ): reduces the recurrence of the tumor, disease progression by 34%.Лечение рака мочевого пузыря остается сложной задачей при которой должен использоваться комплексный подход, включающий удаление опухоли, профилактику рецидивов новообразования, диспансерное наблюдение. Внутрипузырная терапия используется в лечении поверхностного переходно-клеточного рака мочевого пузыря (Та, Т1 и карциномы in situ) с целью лечения существующей или остаточной опухоли, профилактики рецидивов, предотвращения прогрессии заболевания и продления жизни пациентов. Первичная стадия заболевания и степень дифференцированности опухоли остаются важными факторами, определяющими прогноз заболевания, независимо от лечения. По данным клиники урологии УГМА, внутрипузырная химиотерапия снижает рецидивы рака мочевого пузыря на 22%. В настоящее время иммунотерапия БЦЖ остается наиболее эффективным методом лечения и профилактики переходно-клеточного рака мочевого пузыря (Та, Т1, карциномы in situ): позволяет уменьшить количество рецидивов опухоли, прогрессирование заболевания на 34%

Polarization attractors in harmonic mode-locked fiber laser

We report on a polarimetry of harmonic mode-locked erbium-doped fiber laser with carbon nanotubes saturable absorber. We find new types of vector solitons with locked, switching and precessing states of polarization. The underlying physics presents interplay between birefringence of a laser cavity created by polarization controller along with light induced anisotropy caused by polarization hole burning