MRI: Acquisition of a High-Power Narrow-Band Tunable Laser System for Use in Physics Research

该合同支持购买相干MBR-110钛：蓝宝石（Ti:S）连续波激光器，并附带泵浦激光器、光学工作台和诊断设备，用于超冷原子物理、具有金刚石氮空位中心的量子信息科学和垂直腔表面发射激光器的注入动力学。Lundblad教授将使用从玻色-爱因斯坦凝聚态加载到光学晶格中的超冷原子来探索模拟或类似于我们知之甚少的凝聚态物质系统的系统，例如那些涉及高tc超导和量子磁性的系统。基于之前双阱晶格和自旋依赖晶格的经验，他将探索非标准几何和拓扑晶格中的强相关多体物理：三角形和蜂窝晶格，以及具有环状单点波函数的射频修饰晶格。Childress教授将研究金刚石中氮空位（NV）缺陷中心作为量子信息科学的前沿系统。特别是，NV自旋自由度是一个通用的单自旋系统，很容易用光学和微波激发来制备、控制和检测。她将在自制的共聚焦装置中使用刺激发射耗尽（STED）技术进行亚波长成像方法，利用STED与单个NV中心一起使用的天然优势。该研究还集中在改进对基于sted成像的条件下NV自旋动力学的理解。林教授将使用该设备研究垂直腔面发射激光器（VCSEL）的注入动力学，特别是旨在了解多模态下光注入的非线性动力学，并着眼于通过VCSEL同步在基于混沌的安全通信中的应用。Ti:S激光系统的特殊特性——多瓦功率、300nm调谐能力和低于100khz的光谱纯度——使所有研究人员的研究目标得以实现。Ti:S激光系统的收购对贝茨大学的本科研究和教育以及地方、州和国家的研究基础设施产生了广泛的影响。本科生研究是贝茨大学科学课程的核心组成部分，通过独立学习、暑期研究实习和必修的毕业论文项目来体验。这些研究经历对贝茨学院的作用至关重要，因为它将不成比例的大量学生送进了科学领域的研究生学习——这是为技术和经济发展提供必要的训练有素的人才的管道。除了提案中提到的三名研究人员外，所要求的激光系统每年将被6到12名本科研究人员使用，并可能通过课程使用更多。激光系统对相关教师的研究活动非常重要，从而增加了学术活动，与其他机构的合作，并在全州和全国范围内曝光了在贝茨进行的科学工作。贝茨对研究的机构承诺与校外资金相结合，使贝茨的教师能够在高水平的学术活动中开展工作，现场最先进的仪器确保了这种活动将继续有增无减。因此，贝茨的学生（其中许多是代表性不足的群体的成员）既可以通过直接使用设备进行研究，也可以通过广泛接触活跃、充满活力、设备齐全的研究环境来影响设备。

This award supports the purchase of a Coherent MBR-110 titanium:sapphire(Ti:S) continuous-wave laser, with accompanying pump laser, optical table, and diagnostic equipment, for use in ultracold atomic physics, quantum information science with diamond nitrogen-vacancy centers, and injection dynamics of vertical-cavity surface-emitting lasers. Prof. Lundblad will use ultracold atoms loaded from a Bose-Einstein condensate into an optical lattice to explore systems which simulate or behave analogously to poorly-understood condensed-matter systems, e.g. those involved with high-Tc superconductivity and quantum magnetism. Building on previous experience with double-well lattices and spin-dependent lattices, he will explore strongly-correlated many-body physics in lattices of nonstandard geometry and topology: the triangle and honeycomb lattices, and radiofrequency-dressed lattices with ring-like single-site wavefunctions. Prof. Childress will study the nitrogen-vacancy (NV) defect center in diamond as a leading system for quantum information science. In particular, the NV spin degree of freedom is a versatile single spin system readily prepared, controlled, and detected with optical and microwave excitation. She will use stimulated-emission depletion (STED) techniques for subwavelength imaging methods in a homebuilt confocal apparatus, exploiting the natural advantages of STED used with individual NV centers. The research also centers on an improved understanding of NV spin dynamics under conditions necessary for STED-based imaging. Prof. Lin will use the equipment to study injection dynamics in vertical-cavity surface-emitting lasers (VCSELs), specifically aiming to understand the nonlinear dynamics of optical injection in the multimode regime, with an eye towards applications in chaos-based secure communication via VCSEL synchronization. The particular features of the Ti:S laser system - multiwatt power, 300nm tuning capability, and sub-100-kHz spectral purity - enables all of the investigators' research goals. The acquisition of the Ti:S laser system has a broad impact on undergraduate research and education at Bates as well as on local, state, and national research infrastructure. Undergraduate research is a core component of the science curriculum at Bates, experienced through independent study, summer research apprenticeships, and a required senior thesis project. These research experiences are crucial to Bates' role in sending a disproportionately large number of students into postgraduate study in the sciences - the pipeline that provides the trained individuals necessary for technological and economic development. In addition to the three investigators named in this proposal, the requested laser system will be used by six to twelve undergraduate researchers each year, and potentially by more via curricular use. The laser system is important to the research activity of the faculty involved, resulting in increased scholarly activity, collaboration with other institutions, and statewide and national exposure of scientific work being performed at Bates. The institutional commitment to research at Bates in combination with extramural funding allow Bates faculty to operate at a high level of scholarly activity, and the on-site presence of state-of-the-art instrumentation ensures that this activity will continue unabated. The equipment thus impacts Bates students (many of whom are members of underrepresented groups) both through direct use of the apparatus through research, and through broad exposure to an active, vibrant, well-equipped research environment.