Background: Sugar moiety of macromolecules is today very well known for its implications in many biological recognition mechanisms including cell-cell, extracellular matrix-cell and/or bacteria-cell interactions. In t...Background: Sugar moiety of macromolecules is today very well known for its implications in many biological recognition mechanisms including cell-cell, extracellular matrix-cell and/or bacteria-cell interactions. In this context lectins, which are carbohydrate-binding proteins displaying a high affinity for sugar groups of other molecules, are of a great importance, notably in immune response involving bacteria, viruses and fungi. As protein-carbohydrate interactions are often mediated by ions such as calcium, zinc or magnesium, we were prompted to study the effect of a thermal spring water (which contains this type of component) on interactions existing between: 1) osidic receptors of human normal keratinocytes and 2) two lectins greatly implicated in the immune response mechanisms (i.e. the dectin-1 and the langerin), and their ligands. Materials and Methods: In a first series of experiments, we studied the effect of increasing concentrations of a thermal spring water on interactions existing between glycosylated molecules and the osidic receptors expressed at the normal human keratinocytes surface. In a second step, and in order to better understand the putative effect of our thermal spring water on the immune response, we analyzed its effect on the interactions existing between the dectin-1 (implicated in the recognition of bacteria, viruses and fungi) and the langerin (expressed by Langerhans cells, the immune cells of the cutaneous tissue), and their ligands in a model using recombinant human lectins and appropriate binding molecules. Results: We showed here that our thermal spring water was able to reinforce interactions between keratinocytes osidic receptors and some of their ligands, in a dose-related manner: From 8% to 55% of increase with 10% to 30% (v/v) of thermal spring water. In the second part of our studies, we also showed that our thermal spring water was able to modulate interactions between dectin-1 and langerin and their ligands through a biphasic effect: Interactions were enhanced by more than 40% and 20% respectively with 10% of thermal spring water, and return to their basal level or lower for higher concentrations. Conclusion: The tested thermal spring water, probably due to its ionic composition, could significantly affect interactions of osidic receptors with their ligands. This property could be of a great interest to help immune system to maintain an appropriate “vigilance state” by using the thermal water at up to a concentration of 10%, and by avoiding any runaway reaction in case of aggression, by using concentrations higher than 10%. .展开更多
This paper addresses the high dimension sample problem in discriminate analysis under nonparametric and supervised assumptions. Since there is a kind of equivalence between the probabilistic dependence measure and the...This paper addresses the high dimension sample problem in discriminate analysis under nonparametric and supervised assumptions. Since there is a kind of equivalence between the probabilistic dependence measure and the Bayes classification error probability, we propose to use an iterative algorithm to optimize the dimension reduction for classification with a probabilistic approach to achieve the Bayes classifier. The estimated probabilities of different errors encountered along the different phases of the system are realized by the Kernel estimate which is adjusted in a means of the smoothing parameter. Experiment results suggest that the proposed approach performs well.展开更多
In this work, we consider the effect of a small-scale helical driving force on fluid with a stable temperature gradient with Reynolds number . At first glance, this system does not have any instability. However, we sh...In this work, we consider the effect of a small-scale helical driving force on fluid with a stable temperature gradient with Reynolds number . At first glance, this system does not have any instability. However, we show that a large scale vortex instability appears in the fluid despite its stable stratification. In a non-linear mode this instability becomes saturated and gives a large number of stationary spiral vortex structures. Among these structures there is a stationary helical soliton and a kink of the new type. The theory is built on the rigorous asymptotical method of multi-scale development.展开更多
A continuous-wave Nd:KGd(WO4)2 single-longitudinal-mode laser is demonstrated with Fabry-Perot etalons in a simple linear cavity.The thermal lens effect is dramatically lowered by propagating the laser beam along the...A continuous-wave Nd:KGd(WO4)2 single-longitudinal-mode laser is demonstrated with Fabry-Perot etalons in a simple linear cavity.The thermal lens effect is dramatically lowered by propagating the laser beam along the‘athermal’direction inside the laser crystal,which is very beneficial to removing the heat generated in the mode selection process.The maximum single-longitudinal-mode output power obtained is 64.8 mW at incident pump power of 4.7 W,corresponding to an optical conversion efficiency of 1.3%and a slope efficiency of 1.7%.展开更多
The intra-cluster lag consensus means that the agents in the same cluster can achieve lag consensus asymptotically while the agents in different clusters can achieve different consensus.In this paper,the authors inves...The intra-cluster lag consensus means that the agents in the same cluster can achieve lag consensus asymptotically while the agents in different clusters can achieve different consensus.In this paper,the authors investigate the observer-based intra-cluster lag consensus problems of multi-agent systems(MASs)with general linear dynamics and nonlinear dynamics via intermittent adaptive pinning control.The interaction network is considered to be weakly connected,i.e.,it is not necessary to be strongly connected,in-degree balanced or contain a directed spanning tree.To realise the intra-cluster lag consensus,a class of observers is designed to estimate the states of followers.Then a class of observer-based intermittent adaptive pinning control protocols is proposed according to the difference that the agents receive information source.Moreover,the pinning gains are designed to be intermittent adaptive and have an exponential convergence rate,which will effectively reduce communication costs,avoid the pinning gains being larger than those needed in real applications and guarantee the pinning gains quickly converge to steady value.Correspondingly,some sufficient consensus criteria are derived and rigorous proofs are given based on matrix theory and Lyapunov stability theory.Finally,the effectiveness for the proposed intermittent adaptive pinning control strategy is validated by a numerical simulation.展开更多
Structured ultrashort-pulse laser beams, and in particular eigenmodes of the paraxial Helmholtz equation, are currently extensively studied for novel potential applications in various fields, e.g., laser plasma accele...Structured ultrashort-pulse laser beams, and in particular eigenmodes of the paraxial Helmholtz equation, are currently extensively studied for novel potential applications in various fields, e.g., laser plasma acceleration,attosecond science, and fine micromachining. To extend these prospects further, in the present work we push forward the advancement of such femtosecond structured laser sources into the 2-μm spectral region. Ultrashortpulse Hermite– and Laguerre–Gaussian laser modes both with a pulse duration around 100 fs are successfully produced from a compact solid-state laser in combination with a simple single-cylindrical-lens converter. The negligible beam astigmatism, the broad optical spectra, and the almost chirp-free pulses emphasize the high reliability of this laser source. This work, as a proof of principle study, paves the way toward few-cycle pulse generation of optical vortices at 2 μm. The presented light source can enable new research in the fields of interaction with organic materials, next generation optical detection, and optical vortex infrared supercontinuum.展开更多
A mode-locked laser based on a Tm:CNNGG disordered crystal as an active medium and a single-walled carbon nanotube saturable absorber is demonstrated, operating at a central wavelength of 2018 nm. Transformlimited 84 ...A mode-locked laser based on a Tm:CNNGG disordered crystal as an active medium and a single-walled carbon nanotube saturable absorber is demonstrated, operating at a central wavelength of 2018 nm. Transformlimited 84 fs pulses are generated with an average output power of 22 mW at a repetition rate of ~90 MHz.A maximum output power of 98 mW is obtained at a slightly longer pulse duration of 114 fs.展开更多
We report on a high-power Ho:YAG single-crystal fiber(SCF)laser inband pumped by a high-brightness Tm-fiber laser at 1908 nm.The Ho:YAG SCF grown by the micro-pulling-down technique exhibits a propagation loss of 0.05...We report on a high-power Ho:YAG single-crystal fiber(SCF)laser inband pumped by a high-brightness Tm-fiber laser at 1908 nm.The Ho:YAG SCF grown by the micro-pulling-down technique exhibits a propagation loss of 0.05±0.005 cm^-1 at 2.09μm.A continuous-wave output power of 35.2 W is achieved with a slope efficiency of 42.7%,which is to the best of our knowledge the highest power ever reported from an SCF-based laser in the 2µm spectral range.展开更多
Surface channel waveguides(WGs) were fabricated in a monoclinic Tm^(3+):KLu(WO_4)_2 crystal by femtosecond direct laser writing(fs-DLW). The WGs consisted of a half-ring cladding with diameters of 50 and 60 μm locate...Surface channel waveguides(WGs) were fabricated in a monoclinic Tm^(3+):KLu(WO_4)_2 crystal by femtosecond direct laser writing(fs-DLW). The WGs consisted of a half-ring cladding with diameters of 50 and 60 μm located just beneath the crystal surface. They were characterized by confocal laser microscopy and μ-Raman spectroscopy,indicating a reduced crystallinity and stress-induced birefringence of the WG cladding. In continuous-wave(CW)mode, under Ti:sapphire laser pumping at 802 nm, the maximum output power reached 171.1 mW at 1847.4 nm,corresponding to a slope efficiency η of 37.8% for the 60 μm diameter WG. The WG propagation loss was0.7 0.3 d B∕cm. The top surface of the WGs was spin-coated by a polymethyl methacrylate film containing randomly oriented(spaghetti-like) arc-discharge single-walled carbon nanotubes serving as a saturable absorber based on evanescent field coupling. Stable passively Q-switched(PQS) operation was achieved. The PQS60 μm diameter WG laser generated a record output power of 150 m W at 1846.8 nm with η = 34.6%. The conversion efficiency with respect to the CW mode was 87.6%. The best pulse characteristics(energy/duration)were 105.6 nJ/98 ns at a repetition rate of 1.42 MHz.展开更多
Expanding the functionalities of plasmon-assisted lasers is essential for emergent applications in nanoscience and nanotechnology.Here,we report on a novel ability of plasmonic structures to induce dual-wavelength las...Expanding the functionalities of plasmon-assisted lasers is essential for emergent applications in nanoscience and nanotechnology.Here,we report on a novel ability of plasmonic structures to induce dual-wavelength lasing in the near-infrared region in a Yb^(3+) solid-state laser.By means of the effects of disordered plasmonic networks deposited on the surface of a Yb^(3+)-doped nonlinear RTP crystal,room-temperature dual-wavelength lasing,with a frequency difference between the lines in the THz range,is realized.The dual-wavelength laser is produced by the simultaneous activation of two lasing channels,namely,an electronic-and a phonon-terminated laser transition.The latter is enabled by the out-of-plane field components that are generated by the plasmonic structures,which excite specific Raman modes.Additionally,multiline radiation at three different wavelengths is demonstrated in the visible spectral region via two self-frequency conversion processes,which occur in the vicinities of the plasmonic structures.The results demonstrate the potential of plasmonic nanostructures for inducing drastic modifications in the operational mode of a solid-state laser and hold promise for applications in a variety of fields,including multiplexing,precise spectroscopies,and THz radiation generation via a simple and cost-effective procedure.展开更多
We report on a power-scalable sub-100-fs laser in the 2-μm spectral range using a Tm;-doped‘mixed’(Lu,Sc);O;sesquioxide ceramic as an active medium.Pulses as short as 58 fs at 2076 nm with an average output power o...We report on a power-scalable sub-100-fs laser in the 2-μm spectral range using a Tm;-doped‘mixed’(Lu,Sc);O;sesquioxide ceramic as an active medium.Pulses as short as 58 fs at 2076 nm with an average output power of 114 mW at a pulse repetition rate of approximately 82.9 MHz are generated by employing single-walled carbon nanotubes as a saturable absorber.A higher average power of 350 m W at 2075 nm is obtained at the expense of the pulse duration(65 fs).A maximum average power of 486 mW is achieved for a pulse duration of 98 fs and an optical conversion efficiency of 22.3%,representing the highest value ever reported from sub-100-fs mode-locked Tm lasers.展开更多
We demonstrate multi-gigahertz continuous-wave mode-locking of a Yb:KLuW waveguide laser. A femtosecondlaser-inscribed Yb:KLuW channel waveguide in an extended laser cavity delivers a fundamentally mode-locked laser n...We demonstrate multi-gigahertz continuous-wave mode-locking of a Yb:KLuW waveguide laser. A femtosecondlaser-inscribed Yb:KLuW channel waveguide in an extended laser cavity delivers a fundamentally mode-locked laser near 1030 nm. A tunable few-centimeter-long cavity containing a single-walled carbon nanotube saturable absorber as mode-locker generates self-starting femtosecond pulses with average output powers exceeding210 mW at repetition rates of 2.27, 2.69, and 3.55 GHz. The laser cavity, which includes a wedged waveguide,is extended by using a lens pair that controls the laser fluence on the saturable absorber for reliable mode-locked operation without instability. The presented laser performance, mode-locked up to 3.55 GHz, highly suggests the potential of crystalline Yb:KLuW waveguides for realizing high-power ultrafast lasers with higher GHz repetition rates in a quasi-monolithic cavity.展开更多
文摘Background: Sugar moiety of macromolecules is today very well known for its implications in many biological recognition mechanisms including cell-cell, extracellular matrix-cell and/or bacteria-cell interactions. In this context lectins, which are carbohydrate-binding proteins displaying a high affinity for sugar groups of other molecules, are of a great importance, notably in immune response involving bacteria, viruses and fungi. As protein-carbohydrate interactions are often mediated by ions such as calcium, zinc or magnesium, we were prompted to study the effect of a thermal spring water (which contains this type of component) on interactions existing between: 1) osidic receptors of human normal keratinocytes and 2) two lectins greatly implicated in the immune response mechanisms (i.e. the dectin-1 and the langerin), and their ligands. Materials and Methods: In a first series of experiments, we studied the effect of increasing concentrations of a thermal spring water on interactions existing between glycosylated molecules and the osidic receptors expressed at the normal human keratinocytes surface. In a second step, and in order to better understand the putative effect of our thermal spring water on the immune response, we analyzed its effect on the interactions existing between the dectin-1 (implicated in the recognition of bacteria, viruses and fungi) and the langerin (expressed by Langerhans cells, the immune cells of the cutaneous tissue), and their ligands in a model using recombinant human lectins and appropriate binding molecules. Results: We showed here that our thermal spring water was able to reinforce interactions between keratinocytes osidic receptors and some of their ligands, in a dose-related manner: From 8% to 55% of increase with 10% to 30% (v/v) of thermal spring water. In the second part of our studies, we also showed that our thermal spring water was able to modulate interactions between dectin-1 and langerin and their ligands through a biphasic effect: Interactions were enhanced by more than 40% and 20% respectively with 10% of thermal spring water, and return to their basal level or lower for higher concentrations. Conclusion: The tested thermal spring water, probably due to its ionic composition, could significantly affect interactions of osidic receptors with their ligands. This property could be of a great interest to help immune system to maintain an appropriate “vigilance state” by using the thermal water at up to a concentration of 10%, and by avoiding any runaway reaction in case of aggression, by using concentrations higher than 10%. .
文摘This paper addresses the high dimension sample problem in discriminate analysis under nonparametric and supervised assumptions. Since there is a kind of equivalence between the probabilistic dependence measure and the Bayes classification error probability, we propose to use an iterative algorithm to optimize the dimension reduction for classification with a probabilistic approach to achieve the Bayes classifier. The estimated probabilities of different errors encountered along the different phases of the system are realized by the Kernel estimate which is adjusted in a means of the smoothing parameter. Experiment results suggest that the proposed approach performs well.
文摘In this work, we consider the effect of a small-scale helical driving force on fluid with a stable temperature gradient with Reynolds number . At first glance, this system does not have any instability. However, we show that a large scale vortex instability appears in the fluid despite its stable stratification. In a non-linear mode this instability becomes saturated and gives a large number of stationary spiral vortex structures. Among these structures there is a stationary helical soliton and a kink of the new type. The theory is built on the rigorous asymptotical method of multi-scale development.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11674273 and 61805209).
文摘A continuous-wave Nd:KGd(WO4)2 single-longitudinal-mode laser is demonstrated with Fabry-Perot etalons in a simple linear cavity.The thermal lens effect is dramatically lowered by propagating the laser beam along the‘athermal’direction inside the laser crystal,which is very beneficial to removing the heat generated in the mode selection process.The maximum single-longitudinal-mode output power obtained is 64.8 mW at incident pump power of 4.7 W,corresponding to an optical conversion efficiency of 1.3%and a slope efficiency of 1.7%.
基金supported in part by the National Natural Science Foundation of China under Grant Nos.61977004 and 61503016in part by the Fundamental Research Funds for the Central Universities under Grant Nos.YWF20-BJ-J-634 and YWF-19-BJ-J-259。
文摘The intra-cluster lag consensus means that the agents in the same cluster can achieve lag consensus asymptotically while the agents in different clusters can achieve different consensus.In this paper,the authors investigate the observer-based intra-cluster lag consensus problems of multi-agent systems(MASs)with general linear dynamics and nonlinear dynamics via intermittent adaptive pinning control.The interaction network is considered to be weakly connected,i.e.,it is not necessary to be strongly connected,in-degree balanced or contain a directed spanning tree.To realise the intra-cluster lag consensus,a class of observers is designed to estimate the states of followers.Then a class of observer-based intermittent adaptive pinning control protocols is proposed according to the difference that the agents receive information source.Moreover,the pinning gains are designed to be intermittent adaptive and have an exponential convergence rate,which will effectively reduce communication costs,avoid the pinning gains being larger than those needed in real applications and guarantee the pinning gains quickly converge to steady value.Correspondingly,some sufficient consensus criteria are derived and rigorous proofs are given based on matrix theory and Lyapunov stability theory.Finally,the effectiveness for the proposed intermittent adaptive pinning control strategy is validated by a numerical simulation.
基金National Natural Science Foundation of China(51761135115, 52032009, 61975208, 62075090)Deutsche Forschungsgemeinschaft (PE 607/14-1)+3 种基金Laserlab-Europe(654148)Natural Science Foundation of Jiangsu Province(BK20190104)Sino-German Scientist Cooperation and Exchanges Mobility Programme (M-0040)Alexander von Humboldt-Stiftung。
文摘Structured ultrashort-pulse laser beams, and in particular eigenmodes of the paraxial Helmholtz equation, are currently extensively studied for novel potential applications in various fields, e.g., laser plasma acceleration,attosecond science, and fine micromachining. To extend these prospects further, in the present work we push forward the advancement of such femtosecond structured laser sources into the 2-μm spectral region. Ultrashortpulse Hermite– and Laguerre–Gaussian laser modes both with a pulse duration around 100 fs are successfully produced from a compact solid-state laser in combination with a simple single-cylindrical-lens converter. The negligible beam astigmatism, the broad optical spectra, and the almost chirp-free pulses emphasize the high reliability of this laser source. This work, as a proof of principle study, paves the way toward few-cycle pulse generation of optical vortices at 2 μm. The presented light source can enable new research in the fields of interaction with organic materials, next generation optical detection, and optical vortex infrared supercontinuum.
基金National Natural Science Foundation of China(NSFC)(51402268,61505072)Institute of Chemical Materials,China Academy of Engineering Physics(CAEP)(32203)China Scholarship Council(CSC)(201704890003)
文摘A mode-locked laser based on a Tm:CNNGG disordered crystal as an active medium and a single-walled carbon nanotube saturable absorber is demonstrated, operating at a central wavelength of 2018 nm. Transformlimited 84 fs pulses are generated with an average output power of 22 mW at a repetition rate of ~90 MHz.A maximum output power of 98 mW is obtained at a slightly longer pulse duration of 114 fs.
基金Foundation of Deutscher Akademischer Austauschdienst(DAAD)–Research Stays for University Academics and Scientists(57381327)Natural Science Foundation of Jiangsu Province,China(SBK2019030177)+1 种基金China Scholarship Council(201704910363)Foundation of the Government of the Russian Federation(074-U01).
文摘We report on a high-power Ho:YAG single-crystal fiber(SCF)laser inband pumped by a high-brightness Tm-fiber laser at 1908 nm.The Ho:YAG SCF grown by the micro-pulling-down technique exhibits a propagation loss of 0.05±0.005 cm^-1 at 2.09μm.A continuous-wave output power of 35.2 W is achieved with a slope efficiency of 42.7%,which is to the best of our knowledge the highest power ever reported from an SCF-based laser in the 2µm spectral range.
基金Ministerio de Economía y Competitividad(MINECO)(FIS2013-44174-P,FIS2015-71933-REDT,MAT2016-75716-C2-1-R(AEI/FEDER,UE),TEC2014-55948-R)Agència de Gestiód’Ajuts Universitaris i de Recerca(AGAUR)(2017SGR755)+1 种基金Consejería de Educación,Junta de Castilla y León(SA046U16,UIC016)Generalitat de Catalunya(2016FI_B00844,2017FI_B100158,2018FI_B2 00123)
文摘Surface channel waveguides(WGs) were fabricated in a monoclinic Tm^(3+):KLu(WO_4)_2 crystal by femtosecond direct laser writing(fs-DLW). The WGs consisted of a half-ring cladding with diameters of 50 and 60 μm located just beneath the crystal surface. They were characterized by confocal laser microscopy and μ-Raman spectroscopy,indicating a reduced crystallinity and stress-induced birefringence of the WG cladding. In continuous-wave(CW)mode, under Ti:sapphire laser pumping at 802 nm, the maximum output power reached 171.1 mW at 1847.4 nm,corresponding to a slope efficiency η of 37.8% for the 60 μm diameter WG. The WG propagation loss was0.7 0.3 d B∕cm. The top surface of the WGs was spin-coated by a polymethyl methacrylate film containing randomly oriented(spaghetti-like) arc-discharge single-walled carbon nanotubes serving as a saturable absorber based on evanescent field coupling. Stable passively Q-switched(PQS) operation was achieved. The PQS60 μm diameter WG laser generated a record output power of 150 m W at 1846.8 nm with η = 34.6%. The conversion efficiency with respect to the CW mode was 87.6%. The best pulse characteristics(energy/duration)were 105.6 nJ/98 ns at a repetition rate of 1.42 MHz.
基金support from the Spanish Government under project MAT2016-76106-RComunidad de Madrid under grant S2013/MIT-2740+4 种基金funding from the Spanish Government under projects MAT2016-75716-C2-1-R(AEI/FEDER,UE)TEC2014-55948-RGeneralitat de Catalunya under project 2017SGR755grant FPU13/02476 from the Spanish Ministry of Educationfinancial support from the Spanish Government,through The“Maria de Maeztu”Programme for Units of Excellence in R&D(MDM-2014-0377)”.
文摘Expanding the functionalities of plasmon-assisted lasers is essential for emergent applications in nanoscience and nanotechnology.Here,we report on a novel ability of plasmonic structures to induce dual-wavelength lasing in the near-infrared region in a Yb^(3+) solid-state laser.By means of the effects of disordered plasmonic networks deposited on the surface of a Yb^(3+)-doped nonlinear RTP crystal,room-temperature dual-wavelength lasing,with a frequency difference between the lines in the THz range,is realized.The dual-wavelength laser is produced by the simultaneous activation of two lasing channels,namely,an electronic-and a phonon-terminated laser transition.The latter is enabled by the out-of-plane field components that are generated by the plasmonic structures,which excite specific Raman modes.Additionally,multiline radiation at three different wavelengths is demonstrated in the visible spectral region via two self-frequency conversion processes,which occur in the vicinities of the plasmonic structures.The results demonstrate the potential of plasmonic nanostructures for inducing drastic modifications in the operational mode of a solid-state laser and hold promise for applications in a variety of fields,including multiplexing,precise spectroscopies,and THz radiation generation via a simple and cost-effective procedure.
基金partly supported by the National Natural Science Foundation of China(NSFC)(52032009,61975208,62075090,51761135115,61575199,61850410533,and 52072351)Deutsche Forschungsgemeinschaft(PE 607/14-1)+6 种基金Sino-German Scientist Cooperation and Exchanges Mobility Program(M-0040)Natural Science Foundation of Jiangsu Province(BK20190104)National Research Foundation of Korea(2020R1A4A2002828)CAS Key Laboratory of Optoelectronic Materials Chemistry and Physics,FJIRSM CAS(2008DP173016)Foundation of the President of China Academy of Engineering Physics(YZJJLX2018005)State Key Laboratory of Crystal Materials(SKLCM),SDU(KF2001)financial support from the Alexander von Humboldt Foundation through a Humboldt fellowship。
文摘We report on a power-scalable sub-100-fs laser in the 2-μm spectral range using a Tm;-doped‘mixed’(Lu,Sc);O;sesquioxide ceramic as an active medium.Pulses as short as 58 fs at 2076 nm with an average output power of 114 mW at a pulse repetition rate of approximately 82.9 MHz are generated by employing single-walled carbon nanotubes as a saturable absorber.A higher average power of 350 m W at 2075 nm is obtained at the expense of the pulse duration(65 fs).A maximum average power of 486 mW is achieved for a pulse duration of 98 fs and an optical conversion efficiency of 22.3%,representing the highest value ever reported from sub-100-fs mode-locked Tm lasers.
基金National Research Foundation of Korea(2018H1A2A1061480,2019R1A2C3003504,2020R1A4A2002828)MCIN/Agencia Estatal de Investigación(PID2019-108543RB-I00,PID2020-119818GB-I00)Junta de Castilla y León(SA136P20)。
文摘We demonstrate multi-gigahertz continuous-wave mode-locking of a Yb:KLuW waveguide laser. A femtosecondlaser-inscribed Yb:KLuW channel waveguide in an extended laser cavity delivers a fundamentally mode-locked laser near 1030 nm. A tunable few-centimeter-long cavity containing a single-walled carbon nanotube saturable absorber as mode-locker generates self-starting femtosecond pulses with average output powers exceeding210 mW at repetition rates of 2.27, 2.69, and 3.55 GHz. The laser cavity, which includes a wedged waveguide,is extended by using a lens pair that controls the laser fluence on the saturable absorber for reliable mode-locked operation without instability. The presented laser performance, mode-locked up to 3.55 GHz, highly suggests the potential of crystalline Yb:KLuW waveguides for realizing high-power ultrafast lasers with higher GHz repetition rates in a quasi-monolithic cavity.