In this paper,we have proposed and demonstrated the generation of passively mode-locked pulses and dissipative soliton resonance in an erbium-doped fiber laser based on Fe3O4 nanoparticles as saturable absorbers.We ob...In this paper,we have proposed and demonstrated the generation of passively mode-locked pulses and dissipative soliton resonance in an erbium-doped fiber laser based on Fe3O4 nanoparticles as saturable absorbers.We obtained self-starting mode-locked pulses with fundamental repetition frequency of 7.69 MHz and center wavelength of 1561 nm.The output of a pulsed laser has spectral width of 0.69 nm and pulse duration of 14 ns with rectangular pulse profile at the pump power of 190 mW.As far as we know,this is the first time that Fe3O4 nanoparticles have been developed as low-dimensional materials for passive mode-locking with rectangular pulse.Our experiments have confirmed that Fe3O4 has a wide prospect as a nonlinear photonics device for ultrafast fiber laser applications.展开更多
Fe3O4 nano-whiskers were synthesized via ultrasonic-aided reduction of FeCl2.4H2O with N2H4-H2O in concentrated NaOH solution. Phase identification and morphology observation were conducted by X-ray diffraction （XRD...Fe3O4 nano-whiskers were synthesized via ultrasonic-aided reduction of FeCl2.4H2O with N2H4-H2O in concentrated NaOH solution. Phase identification and morphology observation were conducted by X-ray diffraction （XRD） analysis, transmission electron microscopy （TEM） and field emission scanning electron microscopy （FE-SEM）. Face scanning energy dispersive spectrum （face scanning EDS） and twodimensional fast Fourier transform （2DFFF） for element distribution were carried out for confirming composition homogeneity. From XRD and TEIVI, the synthesized Fe304 nano-whiskers are of cubic phase with average dimension of 20 nm~ 200 nm （average aspect ratio of 10）. FE-SEM shows that the nanowhiskers without dispersion are interconnected into a network at a scale of 20μm. 2DFFT of the distribution of Fe and O from face scanning EDS confirms the composition homogeneity of the synthesized Fe3O4. Hydrazine hydrate determines the formation of the nano-whiskers, while the possible mechanism is the preferred growth along certain orientation with the aid of ultrasonic treatment.展开更多
Highly uniform and tight adhering of Fe3O4 particles on carbon fiber film（Fe3O4/CFF） is achieved through a simple in-situ thermal oxidation method. Particularly, 3D CFF with interconnected structure can shorten tran...Highly uniform and tight adhering of Fe3O4 particles on carbon fiber film（Fe3O4/CFF） is achieved through a simple in-situ thermal oxidation method. Particularly, 3D CFF with interconnected structure can shorten transfer path and buffer the volume expansion during charge-discharge cycling. Herein, the obtained Fe3O4/CFF anode exhibits a stable cycling performance and excellent high rate capability. The cell delivers a reversible capacity of 1 711 m A·g^（–1） at a current density of 100 m A·g^（–1） after 100 cycles. Even at a high rate density of 2 A·g^（–1）, the specific capacity also can maintain 1034 m A·g^（–1） after 100 cycles. The simplified fabrication is featured with low-cost and this binder-free perspective holds great potential in mass-production of high-performance metal oxide electrochemical devices.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.61605106)Funded projects for the Academic Leader and Academic Backbones,Shaanxi Normal University(No.18QNGG006)+3 种基金Shaanxi International Cooperation Project(No.2020KW-005)Starting Grants of Shaanxi Normal University(Nos.1112010209 and 1110010717)Open Research Fund of State Key Laboratory of Transient Optics and Photonics,Chinese Academy of Sciences(No.SKLST201809)Fundamental Research Funds for the Central Universities(Nos.GK201802006 and 2018CSLY005).
文摘In this paper,we have proposed and demonstrated the generation of passively mode-locked pulses and dissipative soliton resonance in an erbium-doped fiber laser based on Fe3O4 nanoparticles as saturable absorbers.We obtained self-starting mode-locked pulses with fundamental repetition frequency of 7.69 MHz and center wavelength of 1561 nm.The output of a pulsed laser has spectral width of 0.69 nm and pulse duration of 14 ns with rectangular pulse profile at the pump power of 190 mW.As far as we know,this is the first time that Fe3O4 nanoparticles have been developed as low-dimensional materials for passive mode-locking with rectangular pulse.Our experiments have confirmed that Fe3O4 has a wide prospect as a nonlinear photonics device for ultrafast fiber laser applications.
文摘Fe3O4 nano-whiskers were synthesized via ultrasonic-aided reduction of FeCl2.4H2O with N2H4-H2O in concentrated NaOH solution. Phase identification and morphology observation were conducted by X-ray diffraction （XRD） analysis, transmission electron microscopy （TEM） and field emission scanning electron microscopy （FE-SEM）. Face scanning energy dispersive spectrum （face scanning EDS） and twodimensional fast Fourier transform （2DFFF） for element distribution were carried out for confirming composition homogeneity. From XRD and TEIVI, the synthesized Fe304 nano-whiskers are of cubic phase with average dimension of 20 nm~ 200 nm （average aspect ratio of 10）. FE-SEM shows that the nanowhiskers without dispersion are interconnected into a network at a scale of 20μm. 2DFFT of the distribution of Fe and O from face scanning EDS confirms the composition homogeneity of the synthesized Fe3O4. Hydrazine hydrate determines the formation of the nano-whiskers, while the possible mechanism is the preferred growth along certain orientation with the aid of ultrasonic treatment.
基金Supported by the National Natural Science Foundation of China(21471119)
文摘Highly uniform and tight adhering of Fe3O4 particles on carbon fiber film（Fe3O4/CFF） is achieved through a simple in-situ thermal oxidation method. Particularly, 3D CFF with interconnected structure can shorten transfer path and buffer the volume expansion during charge-discharge cycling. Herein, the obtained Fe3O4/CFF anode exhibits a stable cycling performance and excellent high rate capability. The cell delivers a reversible capacity of 1 711 m A·g^（–1） at a current density of 100 m A·g^（–1） after 100 cycles. Even at a high rate density of 2 A·g^（–1）, the specific capacity also can maintain 1034 m A·g^（–1） after 100 cycles. The simplified fabrication is featured with low-cost and this binder-free perspective holds great potential in mass-production of high-performance metal oxide electrochemical devices.
