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C. I. Rablau J. -O. Ndap X. Ma A. Burger N. C. Giles 《Journal of Electronic Materials》1999,28(6):678-682
ZnSe:Cr2+ is an attractive candidate as a room-temperature tunable solid-state laser with output in the 2–3 μm range. Passive absorption
losses in this emission range currently limit laser performance. In this study, we use absorption and photoluminescence spectroscopies
at 5 and 296K to address the origin of these optical losses. A series of diffusion-doped ZnSe:Cr single-crystal samples with
Cr2+ concentrations in the range from 2×1017 cm−3 to 9×1019 cm−3 were obtained using CrSe powder as the dopant source. We find that trace amounts of Fe2+ produce absorption in the 2–3 μm range. Also, we have obtained data on a 680 nm absorption band observed in ZnSe:Cr which
has been assigned to an internal transition of Cr2+. In our series of samples, the relative intensities of the 680 nm absorption band do not track the relative intensities of
the 1.8 μm band (known to be due to Cr2+), although excitation near 680 nm does produce weak Cr2+ luminescence. Our absorption data do not support the current assignment of the 680 nm absorption as being an internal transition
of the Cr2+ ion. 相似文献
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四价铬离子可调谐激光器研究的进展 总被引:1,自引:0,他引:1
本文主要介绍了两种掺四价铬离子(Cr4+)可调谐激光器─-掺Cr4+镁橄榄石激光器和掺Cr4+钇铝石榴石激光器的进展,着重叙述了其光谱特性和激光特性,并对正发展中的几种新的掺Cr4+激光材料做了简要的评述。 相似文献
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B. L. Vanmil A. J. Ptak L. Bai Lijun Wang M. Chirila N. C. Giles T. H. Myers Larry Wang 《Journal of Electronic Materials》2002,31(7):770-775
Epitaxial ZnSe layers were grown by molecular beam epitaxy (MBE) to study Cr incorporation with the long-term goal of demonstrating
an alternate route for achieving transition-metal-doped lasers. Concentrations between 1015 atoms cm−3 and 4×1020 atoms cm−3 were achieved. Secondary ion-mass spectroscopy (SIMS) concentration profiles strongly suggest that surface segregation and
accumulation of Cr occurs during growth. Photoluminescence (PL) measurements indicate Cr is incorporated in the optically
active Cr2+ state up to levels of ∼1019 cm−3. Electron paramagnetic resonance (EPR) studies suggest that the Cr atoms exhibit collective magnetic behavior even at these
levels. X-ray diffraction (XRD) and reflection high-energy electron diffraction (RHEED) indicate high structural quality is
maintained for Cr incorporation for levels up to ∼1019 atoms cm−3. 相似文献
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J. -O. Ndap C. I. Rablau K. Morrow O. O. Adetunji V. A. Johnson K. Chattopadhyay R. H. Page A. Burger 《Journal of Electronic Materials》2002,31(7):802-805
The maximum optical-absorption cross section of Cr2+ ions was evaluated from near-infrared (NIR) absorption spectroscopy and direct measurements of the chromium concentration
in Cr2+:CdSe crystals. The emission lifetime of the excited state, 5E, of Cr2+ was measured as a function of Cr2+ concentration in the 2×1017 −2×1018 ions/cm3 range and as a function of temperature from 77–300 K. Lifetime values were as high as ∼6 μs in the 77–250 K range and decreased
to ∼4 μs at 300 K because of nonradiative decays. Assuming that most of the Cr dopant is in the Cr2+ state, an optical-absorption cross section σa of (1.94±0.56) × 10−18 cm2 was calculated. Implications for laser performance are discussed. 相似文献
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Cr4 :YAG晶体具有良好的物理化学性质 ,其在激光器的研究中有着十分重要的作用 ,这篇文章第一次全面概括了Cr4 :YAG晶体在固体激光器中的三种应用。Cr4 :YAG晶体既可作为调Q晶体用于其它固体激光器中 ,用来改善输出激光的性能 ,同时它也可作为激光增益介质 ,制作成宽带可调谐的激光器系统 ,用于光纤通信技术、量子通信、光电子器件等等当中。 相似文献
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Cr2+:ZnSe中红外激光器 总被引:2,自引:0,他引:2
Cr2 掺杂Ⅱ-Ⅵ族化合物在中红外波段的输出,在气体检测、遥感、通信、眼科医学、神经外科等领域有着重要的应用前景.目前已经获得了最大1.7 W的连续输出功率,18.5 W的平均脉冲功率,1100 nm的调谐范围和最窄4 ps的脉宽.对Cr2 :ZnSe连续、脉冲、随机纳米激光器以及其它的Cr2 掺杂Ⅱ-Ⅵ族化合物激光器的最新的国内外研究进展进行了综述. 相似文献
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A. G. Bluiett U. Hömmerich R. T. Shah S. B. Trivedi S. W. Kutcher C. C. Wang 《Journal of Electronic Materials》2002,31(7):806-810
We are engaged in a systematic study of the optical and laser properties of Cr2+-doped cadmium chalcogenides. Previously, we demonstrated quasi-continuous wave lasing from Cr2+-doped Cd0.55Mn0.45Te with slope efficiencies as high as 64% and a laser tuning range from 2,170–3,010 nm. In this paper, we report the first
demonstration of lasing from Cr:CdTe at room temperature. Pulsed-laser operation was obtained with a free-running spectrum
centered at 2,535 nm. The slope efficiency of the laser was low (∼1%) because of large parasitic losses at the laser wavelength.
The spectroscopic properties of Cr:CdTe are favorable for laser applications because of a large emission cross section (∼2.5
× 10−18 cm2) and a high emission-quantum yield (∼88%). In addition, CdTe can easily incorporate Cr ions either through melt growth or
diffusion doping. Along with our results on Cr2+:CdTe, we report on the optical properties of several other Cr2+-doped II-VI semiconductors (ZnS, ZnSe, ZnTe, CdS, CdSe, CdTe, Cd0.9Zn0.1Te, Cd0.65Mg0.35Te, Cd0.85Mn0.15Te, and Cd0.55Mn0.45Te) and compare them for applications as solid-state laser materials. 相似文献
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可调谐连续波Cr:LiSAF激光器的研究 总被引:7,自引:0,他引:7
报道了连续波运转的Cr:LiSAF激光器。该器件采用氩离子激光器的488nm谱线泵浦Φ6mm×20mm的Cr:LiSAF晶体,在吸收泵浦功率为900mW时,得到50mW的连续波输出。当在腔内放置色散元件后,其调谐范围是820nm到865nm。 相似文献
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Ming Luo B. L. Vanmil R. P. Tompkins Y. Cui T. Mounts U. N. Roy A. Burger T. H. Myers N. C. Giles 《Journal of Electronic Materials》2003,32(7):737-741
Incorporation of Cr into ZnTe epilayers grown by molecular-beam epitaxy (MBE) is reported. Photoluminescence (PL) using both
continuous wave (CW) and pulsed-excitation sources is used to characterize the radiative efficiency of doped layers in the
infrared region. The Cr2+ ions produce a broad emission band peaking in the 2–3 μm range, which is of potential use in tunable-laser devices. The optimum
Cr concentration for achieving bright, room-temperature infrared emission was found to be in the range from low- to mid-1018 cm−3. Temperature-dependent luminescence studies were performed to determine thermal-quenching activation energies. Using a pulsed-laser
operating at 1.9 μm, an investigation of emission lifetimes was made. The emission-decay curves for the Cr2+ recombination in ZnTe:Cr films could be described by a single exponential and were nearly independent of temperature from
80 K to 300 K. A room-temperature lifetime of ∼2.5 μsec in a ZnTe:Cr layer with [Cr] ∼1.4 × 1018 cm−3 compares favorably with values reported for bulk ZnTe:Cr. 相似文献
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介绍了一种新型的二极管直接抽运的可调谐Cr^4^ :YAG全固化激光器,其输出激光的单脉冲功率最大可达260mW,其波长调谐范围为1356-1553nm,跨度为197nm。 相似文献
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