Nd^(3+)-doped tellurite glass and a single mode tellurite glass fiber with a core diameter of 8 μm were prepared in this work. The 1.33-μm emission from the ~4F_(3/2)→~4I_(13/2) transition of Nd^(3+) with a spectra...Nd^(3+)-doped tellurite glass and a single mode tellurite glass fiber with a core diameter of 8 μm were prepared in this work. The 1.33-μm emission from the ~4F_(3/2)→~4I_(13/2) transition of Nd^(3+) with a spectral bandwidth of 55 nm in tellurite glass fiber is observed. The lifetime of 164 μs of ~4F_(3/2) level and quantum efficiency of about 100% are obtained.展开更多
Intense 2.7-μm emissions are obtained from Er3＋/Nd3＋ co-doped tellurite glass samples under the 808-nm laser diode excitation. According to the absorption spectra, Judd-Ofelt parameters and radiative transition pro...Intense 2.7-μm emissions are obtained from Er3＋/Nd3＋ co-doped tellurite glass samples under the 808-nm laser diode excitation. According to the absorption spectra, Judd-Ofelt parameters and radiative transition probabilities are calculated and analyzed using the Judd-Ofelt theory. The spectroscopic properties and energy transfer mechanism between Er3＋ and Nd3＋ are analyzed. The effects of OH- content on the spectroscopic properties of Er3＋/Nd3＋ co-doped samples are discussed. The obtained results indicate that Er3＋/Nd3＋ co-doped tellurite glass can significantly develop optical properties of 2.7-μm emission, if OH- groups can be effectivelv eliminated.展开更多
Crystallization is induced by pulsed laser irradiation of as-deposited amorphous Ge_2Sb_2Te_5 films. Changes of the irradiated areas have been analyzed with the reflectivity contrast. As laser fluences increasing, the...Crystallization is induced by pulsed laser irradiation of as-deposited amorphous Ge_2Sb_2Te_5 films. Changes of the irradiated areas have been analyzed with the reflectivity contrast. As laser fluences increasing, the reflectivity contrast increases from 0%-2% to 14%-16%, which indicates the structure of asdeposited films transforms from amorphous to crystalline phases. The process of crystallization driven by the movement and rearrangement of atoms is described. And also the influence of the pulse duration on the threshold of crystallization is discussed, the results show that a lower threshold of crystallization can be produced for as-deposited films irradiated by the laser with short pulse duration. However, by the laser with long pulse duration, crystallization can only be formed with a higher threshold. The crystallization of films by irradiation of laser pulses is studied by Raman spectra.展开更多
Spectral characteristics of the amplified spontaneous emission (ASE) from a novel single mode Er^(3+) doped tellurite fiber with D-type cladding is reported in this letter. When pumped at 980 nm, an ASE source that ha...Spectral characteristics of the amplified spontaneous emission (ASE) from a novel single mode Er^(3+) doped tellurite fiber with D-type cladding is reported in this letter. When pumped at 980 nm, an ASE source that has nearly a 100-nm flat FWHM bandwidth is obtained with a fiber length of 30-60 cm. Variation of ASE spectra with pump powers and fiber lengths are measured. Output power up to 2.0 mW is obtained with a launched pump power of 660 mW.展开更多
A superlattice-like (SLL) structure was applied to phase-change optical recording. The recording layer consisting of alternating thin layers of two different phase-change materials, GeTe and Sb2Te3, were grown by magn...A superlattice-like (SLL) structure was applied to phase-change optical recording. The recording layer consisting of alternating thin layers of two different phase-change materials, GeTe and Sb2Te3, were grown by magnetron sputtering on polycarbonate substrates. Land/groove optical recording was adopted to suppress crosstalk and obtain a large track density. Dynamic properties of the SLL disc were investigated with the shortest 1T pulse duration of 8 ns. Clear eye pattern was observed after 10000 direct overwrite cycles. Erasability above 20 dB was achieved at a constant linear velocity of 19 m/s. Carrier-noise ratio (CNR) kept above 46 dB when the recording frequency reaches 21 VIHz. The SLL phase change optical disc demonstrates a better recording performance than the Ge1Sb2Te4 and Ge1Sb4Te7 discs in terms of CNR, erasability, and overwrite jitter.展开更多
Er3＋/Ce3＋ co-doped tellurite-based glasses with composition of TeO2-ZnO-Na2O are prepared by high- temperature melt-quenching technique. Effects of Ce2O3 content on the 1.53 μm band fluorescence spectra and fluores...Er3＋/Ce3＋ co-doped tellurite-based glasses with composition of TeO2-ZnO-Na2O are prepared by high- temperature melt-quenching technique. Effects of Ce2O3 content on the 1.53 μm band fluorescence spectra and fluorescence lifetime of Er3＋ are measured and investigated. It is found that the tellurite glass containing Ce203 with molar concentration of 0.25% exhibits an increment of 13% in 1.53 μm fluorescence intensity and an increment of 15% in the 4I13/2 level lifetime. The results indicate that the prepared tellurite-based glass with a suitable Er3＋/Ce3＋ codoping concentration is an excellent gain medium applied for broadband Er3＋-doped fiber amplifier （EDFA） pumped with a 980 nm laser diode.展开更多
基金This work was supported by the Rising-Star Project (No. 04QMX1448)of Shanghai Municipal Science and Technology Commission and the National Natural Science Foundation of China(No. 60207006)
文摘Nd^(3+)-doped tellurite glass and a single mode tellurite glass fiber with a core diameter of 8 μm were prepared in this work. The 1.33-μm emission from the ~4F_(3/2)→~4I_(13/2) transition of Nd^(3+) with a spectral bandwidth of 55 nm in tellurite glass fiber is observed. The lifetime of 164 μs of ~4F_(3/2) level and quantum efficiency of about 100% are obtained.
基金supported by the National Natural Science Foundation of China under Grant No.51172252.
文摘Intense 2.7-μm emissions are obtained from Er3＋/Nd3＋ co-doped tellurite glass samples under the 808-nm laser diode excitation. According to the absorption spectra, Judd-Ofelt parameters and radiative transition probabilities are calculated and analyzed using the Judd-Ofelt theory. The spectroscopic properties and energy transfer mechanism between Er3＋ and Nd3＋ are analyzed. The effects of OH- content on the spectroscopic properties of Er3＋/Nd3＋ co-doped samples are discussed. The obtained results indicate that Er3＋/Nd3＋ co-doped tellurite glass can significantly develop optical properties of 2.7-μm emission, if OH- groups can be effectivelv eliminated.
文摘Crystallization is induced by pulsed laser irradiation of as-deposited amorphous Ge_2Sb_2Te_5 films. Changes of the irradiated areas have been analyzed with the reflectivity contrast. As laser fluences increasing, the reflectivity contrast increases from 0%-2% to 14%-16%, which indicates the structure of asdeposited films transforms from amorphous to crystalline phases. The process of crystallization driven by the movement and rearrangement of atoms is described. And also the influence of the pulse duration on the threshold of crystallization is discussed, the results show that a lower threshold of crystallization can be produced for as-deposited films irradiated by the laser with short pulse duration. However, by the laser with long pulse duration, crystallization can only be formed with a higher threshold. The crystallization of films by irradiation of laser pulses is studied by Raman spectra.
基金This work was supported by the Rising-Star Project (No. 04QMX1488)of Shanghai Municipal Science and Technology Commission and the National Natural Science Foundation of China(No. 60207006).
文摘Spectral characteristics of the amplified spontaneous emission (ASE) from a novel single mode Er^(3+) doped tellurite fiber with D-type cladding is reported in this letter. When pumped at 980 nm, an ASE source that has nearly a 100-nm flat FWHM bandwidth is obtained with a fiber length of 30-60 cm. Variation of ASE spectra with pump powers and fiber lengths are measured. Output power up to 2.0 mW is obtained with a launched pump power of 660 mW.
基金Work described in the letter was performed at Data Storage Institute, Singapore. The authors gratefully acknowledge the financial support by the National Natural Science Foundation of China under Grant No. 60132030.
文摘A superlattice-like (SLL) structure was applied to phase-change optical recording. The recording layer consisting of alternating thin layers of two different phase-change materials, GeTe and Sb2Te3, were grown by magnetron sputtering on polycarbonate substrates. Land/groove optical recording was adopted to suppress crosstalk and obtain a large track density. Dynamic properties of the SLL disc were investigated with the shortest 1T pulse duration of 8 ns. Clear eye pattern was observed after 10000 direct overwrite cycles. Erasability above 20 dB was achieved at a constant linear velocity of 19 m/s. Carrier-noise ratio (CNR) kept above 46 dB when the recording frequency reaches 21 VIHz. The SLL phase change optical disc demonstrates a better recording performance than the Ge1Sb2Te4 and Ge1Sb4Te7 discs in terms of CNR, erasability, and overwrite jitter.
基金supported by the National Natural Science Foundation of China(No.61178063)the Scientific Research Foundation of Graduate School of Ningbo University(No.G13035)
文摘Er3＋/Ce3＋ co-doped tellurite-based glasses with composition of TeO2-ZnO-Na2O are prepared by high- temperature melt-quenching technique. Effects of Ce2O3 content on the 1.53 μm band fluorescence spectra and fluorescence lifetime of Er3＋ are measured and investigated. It is found that the tellurite glass containing Ce203 with molar concentration of 0.25% exhibits an increment of 13% in 1.53 μm fluorescence intensity and an increment of 15% in the 4I13/2 level lifetime. The results indicate that the prepared tellurite-based glass with a suitable Er3＋/Ce3＋ codoping concentration is an excellent gain medium applied for broadband Er3＋-doped fiber amplifier （EDFA） pumped with a 980 nm laser diode.
