Determination of suitable hosts for Rare-Earth doped planar upconversion waveguide lasers.

确定稀土掺杂平面上转换波导激光器的合适主体。

• 批准号: EP/G003319/1
• 负责人: Martin Charlton
• 金额: $ 37.89万
• 依托单位: University of Southampton
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2009
• 资助国家: 英国
• 起止时间: 2009 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FG003319%2F1
• 关键词: Determination; suitable; hosts; Rare; Earth

Ultimately, we propose to fabricate compact, mass-producible, high-power visible wavelength lasers. These solid-state lasers operate by a process called upconversion which is quite different from the frequency doubling mechanism utilised in green laser pointers . As such, these upconversion lasers represent an innovative and highly disruptive laser technology; a technology that does not currently have a commercial outlet.The upconversion laser scheme to be employed here uses light from cheap, readily available semiconductor lasers operating in the near infrared, and by absorbing 2 or 3 infrared photons excites Rare-Earth ions to a high energy state from where they can emit light at visible wavelengths.The proposed research is necessary in order to identify suitable materials for the key component of the upconversion laser, the low-loss optical waveguide that hosts the gain-providing Rare-Earth element.We propose to carry out this initial research using the well-studied Rare-Earth Praseodymium (Pr) with Ytterbium (Yb) as a co-dopant. We chose Pr for a number of reasons including:1) Emission at multiple visible wavelengths including blue/green, green and red.2) Previous proof of high efficiency upconversion lasing in ZBLAN optical fibres.3) Use of a single wavelength pumping source when co-doped with Ytterbium (Yb).4) The apparent lack of a photodarkening mechanism.In point 4), photodarkening refers to a mechanism associated with upconversion using the Rare-Earth Thulium (Tm) whereby the Tm ion as well as emitting the (wanted) blue photon, also emits an (unwanted) high energy ultraviolet photon that damages - or photodarkens - many host materials. This photodarkening basically increases the optical loss of the host to the point where lasing is not possible (the loss exceeds the gain). It is purely this photodarkening problem that has prevented the commercial use of Tm in upconversion lasers for the blue part of the visible spectrum.Although Praseodymium does not appear to exhibit photodarkening, it does require a low phonon energy host otherwise it will undergo radiationless transitions that severely reduce its emission at optical wavelengths, and makes lasing impossible. Unfortunately, the most commonly used materials for planar optical waveguides typically have peak phonon energies that are too high to accommodate Pr as the active Rare-Earth. Hence, the purpose of this proposed research, to find a suitable low-loss, low phonon energy host material that will enable upconversion lasing using Rare-Earth elements such as Pr.Success in identifying a suitable host material will allow high-power visible wavelength lasers to be mass-produced. This in turn would allow the creation of a new high-technology laser company which would further increase the U.K's profile in this very strategic area.

最终，我们建议制造紧凑、可批量生产的高功率可见光波长激光器。这些固态激光器通过一种称为上转换的过程工作，这与绿色激光指示器中使用的倍频机制有很大不同。因此，这些上转换激光器代表了一种创新的、极具破坏性的激光技术；这是一项目前还没有商业化出口的技术。这里将采用的上转换激光器方案使用廉价的、容易获得的近红外半导体激光器的光，通过吸收2到3个红外光子将稀土离子激发到高能态，在那里它们可以发射可见光波长的光。为了确定上转换激光器的关键部件--容纳提供增益的稀土元素的低损耗光波导--的合适材料，拟议的研究是必要的。我们建议使用研究得很好的稀土PraseDy(Pr)和Yb(Yb)作为共掺杂进行这一初步研究。我们选择Pr有很多原因，包括：1)在包括蓝/绿、绿和红在内的多种可见光波长下的发射。2)ZBLAN光纤中高效上转换激光的先前证明。3)当Yb(Yb)共掺杂时使用单一波长的泵浦光源。4)明显缺乏光变暗机制。在点4)中，光变暗是指与使用稀土Tu(TM)的上转换相关联的机制，根据该机制，Tm离子在发出(想要的)蓝色光子的同时，也发出(不想要的)高能紫外线光子，从而损坏-或者说光变暗-许多宿主材料。这种光变暗基本上将主机的光学损耗增加到不可能进行激光的程度(损耗超过增益)。正是这种光变暗的问题阻碍了Tm在可见光谱的蓝色部分的上转换激光器中的商业应用。尽管Pr似乎没有表现出光变暗，但它确实需要一个低声子能量主体，否则它将经历无辐射的跃迁，严重减少其在光学波长的发射，并使激光不可能。不幸的是，最常用的平面光波导材料通常具有太高的峰值声子能量，不能容纳Pr作为活跃的稀土。因此，这项拟议研究的目的是找到一种合适的低损耗、低声子能量的基质材料，这种基质材料能够实现使用稀土元素的上转换激光，成功地识别出合适的基质材料将使高功率可见波长激光器得以批量生产。这反过来将允许创建一家新的高科技激光公司，这将进一步提高英国在这一非常具有战略意义的领域的形象。

项目成果

Structural characteristics and optical properties of plasma assisted reactive magnetron sputtered dielectric thin films for planar waveguiding applications

• DOI: 10.1016/j.surfcoat.2012.05.110
• 发表时间: 2012-07
• 期刊: Surface & Coatings Technology
• 影响因子: 5.4
• 作者: S. Pearce;M. Charlton;J. Hiltunen;J. Puustinen;J. Lappalainen;J. Wilkinson

Properties of rare earth doped thin film dielectric layers for upconversion laser waveguides

用于上转换激光波导的稀土掺杂薄膜介电层的特性

• DOI: 10.1117/12.883187
• 发表时间: 2011
• 作者: Pearce S

Fabrication of photonic crystals in rare-earth doped chalcogenide glass films for enhanced upconversion

在稀土掺杂硫族化物玻璃薄膜中制造光子晶体以增强上转换

• DOI: 10.1117/12.908014
• 发表时间: 2012
• 作者: Pollard M

Chi 3 dispersion in planar tantalum pentoxide waveguides in the telecommunications window.

• DOI: 10.1364/ol.34.001135
• 发表时间: 2009-04
• 期刊: Optics letters
• 影响因子: 3.6
• 作者: Ruiqi Chen;M. Charlton;P. Lagoudakis

Experimental demonstration of on-chip optical parametric oscillation in planar tantalum pentoxide waveguides

平面五氧化二钽波导片上光学参量振荡的实验演示

• DOI: 10.1117/12.860614
• 发表时间: 2010
• 作者: Chen R