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Navigating Pathways to Success: Improving Outcomes for Rural Community College STEM Scholars through Mentoring and Comprehensive Interventions: Cape Cod Community College

Fredrick Bsharah

[email protected]

Millions of STEM jobs are projected to go unfilled in the future. For low-income, rural, diverse students, a community college can be the only accessible entry point for higher education, a gateway to STEM careers. Unfortunately, these students face complex barriers that decrease their ability to pursue and successfully complete STEM programs. Over five years, Cape Cod Community College's S-STEM program will fund over fifty scholarships to academically talented students with demonstrated financial need in its engineering, computer science, mathematics, and science programs. In addition to financial support, the STEM Scholars program will employ evidence-based strategies of effective mentoring, academic support, cohort-building, and other interventions to help Scholars persist, transfer to four-year degree programs, and prepare them for STEM careers. To achieve program goals, the college will work with regional high schools and transfer universities. The project will focus on increasing access and entry for low-income, rural, and diverse students initially into STEM programs and then into well-paid, in-demand STEM careers.<br/><br/>Project goals are to increase recruitment, retention, completion, and transfer rates in STEM programs among students who are academically talented and have demonstrated financial need. Evidence-based, comprehensive interventions will be used to promote student success. Students will start by attending a cohort-based orientation designed to develop a shared sense of purpose and community. Faculty mentors will have frequent meetings with students to provide career-focused advising, connect students with resources, and discuss any academic or personal issues that may put student success at-risk. In addition, students will participate in scheduled study groups, tutoring, and supplemental instruction. Transfer advising and visits to transfer universities will be initiated during each student's first term. To support STEM profession exploration, the project will offer industry partner mentoring, industry speaker panels, visits to industry job sites, internship and job shadowing opportunities, and attendance at professional conferences. To create a cohort and a sense of connection, the project will offer opportunities for students to socialize and participate in group identity-building activities. Finally, this project will fund scholarships to address student need. As part of their efforts, the project team will seek to determine which activities have the most impact on student retention, completion, and transfer in STEM programs, particularly among rural students, and why. Dissemination of results will take place in publications, online, and through conferences. This project furthers the goals of the NSF's Scholarships in Science, Technology, Engineering, and Mathematics program by increasing the number of low-income academically talented students who earn degrees in STEM fields.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

AwardsFreedom CheteniSchool Administrators ResearchThe Superintendents Journal

Creating STEM Opportunities for High-Achieving Rural Alabama Students: University of North Alabama

Melissa Moore-Driskell

[email protected]

With funding from the NSF Scholarships in Science, Technology, Engineering, and Mathematics (S-STEM) program, this project will provide scholarships to academically promising, low-income students drawn from the Alabama rural catchment region. By engaging local high schools, families, and support systems, this program will develop a pathway for rural students in the region to enroll in STEM programs at the University of North Alabama. Scholars will be provided with a tailored yet diverse breadth of academic and co-curricular opportunities to promote retention, graduation, and success in the STEM workforce. The goal of the program will be for at least 90% of S-STEM scholarship recipients to enter a STEM-related career and/or pursue graduate STEM studies. Graduates of the program will support the growing economic and industrial needs of the region as STEM job growth is expected to increase by over 20% in north Alabama by 2026. The program has the potential to provide innovative best practices that may be used to increase STEM retention, graduation, and workforce development at other institutions that serve rural students.<br/><br/>The S-STEM Scholars program will strive to graduate at least 75% of its Scholars in eight semesters and increase the University of North Alabama's four-year graduation rate by sixteen percentage points. To achieve these goals, Scholars will be offered a well-coordinated blend of academic and co-curricular activities, including college orientation, faculty mentoring and institutional advising, community engagement, career and entrepreneurial opportunities, University support services, and institutional engagement. To determine the effectiveness of program activities on the recruitment, retention, and graduation of STEM students from rural backgrounds, as well as changes in perceptions related to college, belonging, and careers, the current program project will compare S-STEM Scholars (the treatment group) with non-Scholars (control group). The program will use a matched sample approach to identify non-Scholars who share as many characteristics with the treatment group as possible. The differences between the treatment and control groups will be analyzed using a between-subjects and within-subjects design. Specifically, this study will examine if the additional activities offered to Scholars, and the levels of participation by Scholars, result in significant differences in outcomes. The project will use a mixed-method design that will involve collecting, analyzing, and integrating quantitative data from survey questions and qualitative data from focus groups. By using different methods and techniques, it will allow for corroboration of the robustness of the findings and their generalizability to other institutions that serve rural students.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

AwardsFreedom CheteniSchool Administrators ResearchThe Superintendents Journal

10th African Materials Research Society (A-MRS) Conference 2019: Materials Research Society

Eric Garfunkel

[email protected]

This award to the Materials Research Society supports mainly the participation of US based-scientists at the Tenth African Materials Research Society (A-MRS) Conference. The A-MRS conferences bring unique value by pulling together leading international scientists and engineers to discuss recent advances in broad areas of materials research and to help define future research priorities including in areas of critical need for Africa. The themes for the 10th A-MRS conference include materials for energy; health, nanoscience/nanotechnology; agriculture/Environment; sustainable buildings and constructions; computational materials science; and materials for mining and mineral processing. The conference also includes sessions on education/networking in materials science and engineering curriculum development, web-based learning, exchanges, summer schools on manufacturing and structural materials. The themes of the conference appropriately address topics of interest to the global community as well as issues specific to Africa. The funds will support travel and participation costs of students and young scientists currently working in American universities, some support will also be used to bring in leading senior international scientists and African graduate students. The Conference will be held at the Nelson Mandela African Institute of Science and Technology (NM-AIST) in Arusha, Tanzania in December 2019. Organized by the African-MRS with strong support of the Materials Research Society (MRS), the heart of the Conference is to build knowledge, foster relationships and promote action to further the understanding in the broad fields associated with materials science and technology. Similar to past African-MRS Conferences, participants will come from around the world, with an anticipated attendance of 500. The award is from Division of Materials Research and the Office of Multidisciplinary Activities of the Directorate for Mathematical and Physical Sciences.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

AwardsFreedom CheteniSchool Administrators ResearchThe Superintendents Journal

Non-linear THz optical effects as a probe of Berry's phase in topological materials: Johns Hopkins University

Norman Armitage

[email protected]

Non-Technical Abstract:<br/>Most of what we know about materials comes from their response to perturbations at their favorite (natural) frequencies. For instance, the pitch of sound from a plucked violin string depends on its length, the tension in it, and its thickness. In a similar way, the behavior of atoms in materials depends on the natural frequency, which, for many solid materials, fall in the Terahertz spectral range, a very difficult range to access technically until recently. This project takes advantage of recent dramatic technical advances in Terahertz frequencies to probe new materials called topological materials. These materials have been predicted to possess properties that make them useful for developing electronic devices for quantum information technology. This project also includes a broad initiative in education and outreach. The work is of particular educational value in training students with unique skills to prepare them as the work force in high tech industries. The research team will play active roles in the Johns Hopkins Physics Fair- an outreach activity which brings hundreds of people each year through Hopkins' labs during a Saturday event and exposes them to various physics demonstrations and activities. The team will also give demonstration shows at the Physics Fair and work with under-resourced local schools.<br/><br/>Technical Abstract:<br/>This is a project to investigate a number of topological and other material systems that have important Berry phase effects using nonlinear optical response. Topological states of matter have been of central interest in condensed matter physics in recent years, yet we are lacking unique measures of many of these systems' electrodynamic properties. Theory has indicated that the nonlinear response of these compounds can give unique insight into the essential Berry phase structure of their underlying wavefunctions. Measurements will emphasize the extended THz range (here 0.1 – 40 THz [0.4 – 165 meV]) where generally responses target the low energy emergent degrees of freedom, but experiments will use a full complement of photon energies up through the near infrared. Experiments will be performed on both topological materials and trivial materials with important Berry phase effects. Materials include topological insulators, Weyl semimetals, Dirac semimetals, and 2D transition metal dichalcogenides. We will explore the nonlinear response of these system to both linear and circularized polarized radiation in a number of specific configurations that are designed to elucidate their Berry phase structure (Berry curvature and Berry connection) in these compounds. Many theoretical predictions exist, but experimentally, this is an almost completely unexplored area, which aside from its intrinsic importance has the potential to give major new insight into what might have been considered a mature area — the nonlinear response of solids.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

AwardsFreedom CheteniSchool Administrators ResearchThe Superintendents Journal

Doctoral Dissertation Research: Child and Child-Directed Expression of Possession in a Polysynthetic Language: University of Hawaii

Andrea Berez-Kroeker

[email protected]

The scientific field of language acquisition research examines a basic foundation of the human experience: How children come to speak their first language. For decades the field has largely focused on languages with millions (or even billions) of speakers, such as Spanish, French, Japanese, and English. We know very little about how children learn to speak most of the other 7000 languages around the world. Approximately half of these languages are in danger of disappearing, which includes all of the Algonquian language family, one of the largest groups of indigenous languages in North America. Algonquian languages such as Northern East Cree (NEC) are radically different from those typically studied in language acquisition research, and as these languages cease to be spoken, we lose the chance to understand how children acquire the fundamentally human capacity of linguistic expression. This dissertation project explores how children learn to speak NEC, one of the few remaining indigenous languages in North America still learned by children as a first language. This project analyzes and improves video/audio recordings collected by the Chisasibi Child Language Acquisition Study (CCLAS), and this dissertation also includes new fieldwork with adult speakers of NEC to provide more insight into how the language works and the stages children go through when learning the language. This dissertation project offers a range of benefits for science and for communities. It will enhance existing documentation of NEC and include child speech as well as speech from adults to children, both of which are underrepresented genres in language documentation. It will also expand the purview and deepen the diversity of language acquisition research. Furthermore, this dissertation can help provide Cree communities with better tools for language assessment and speech-language pathology, so that children may have better support on their journey to become speakers of their language. Lastly, the documentation and description generated by this dissertation can help inform the development of curricula and teaching materials for learners of the Cree language.<br/><br/>This dissertation will enhance and expand the documentary record of NEC. This project will create new language documentation as well as enrich existing recordings of child and child-directed speech collected by the Chisasibi Child Language Acquisition Study (CCLAS). The focus of this dissertation is the first language acquisition of the expression of possession, which is a fundamental concept in cognitive and linguistic development. This project will create and advance language documentation on two fronts. First, research involves working with adult speakers of NEC to review CCLAS recordings and elicit and transcribe adult-like targets. This will produce hours of transcribed and annotated audio recordings of NEC as well as unique metalinguistic commentary and analysis. Second, these adult targets, transcriptions, elicitations, analysis, commentary, and notes will be used to enrich the existing CCLAS corpus. This work will help enable CCLAS to make additional transcripts, annotations, and media files publicly available. Through this work, this dissertation will help break new scientific ground. For example, this dissertation examines speech genres often absent in language documentation, and it enriches the range and typological diversity of language acquisition research. This project can also provide insight to help ensure that methods and tools in language assessment and speech-language pathology are linguistically and culturally inappropriate. The findings from this research can also inform the creation of curriculum and pedagogical materials to benefit not only second language learners but also meet the needs of schools teaching Cree-speaking children about the structure of their mother tongue.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

AwardsFreedom CheteniSchool Administrators ResearchThe Superintendents Journal

Collaborative Research: Engineering the Chemistry at Solid-Solid Interfaces of Li-O2 Battery Cathodes: Purdue University

Jeffrey Greeley

[email protected]

Lithium-oxygen batteries potentially could have energy storage capacities that rival gasoline fuel, but there remains much fundamental scientific knowledge to learn about these batteries before the technology can be commercialized. In particular, some of the chemical products formed during the operation of the batteries can slowly degrade and poison the materials, leading to performance losses over extended periods of operation. This research project seeks to overcome these problems by exploring a class of inexpensive, mixed metal oxide electrocatalysts that may alter the chemistry of lithium-oxygen batteries. This project aims to develop a framework to engineer the chemistry of lithium-oxygen batteries, which are a potential next-generation energy storage device, and to improve their performance. The studies combine advanced characterization methods and theoretical calculations to determine how the properties of the oxide surfaces influence the products that are produced on lithium-oxygen electrodes. These insights will be leveraged to develop design principles that will aide in identifying oxide electrocatalysts that improve battery cell performance. The researchers involved in this project will partner with local K-12 schools to involve economically disadvantaged students with the proposed research through summer internships and student exchanges. They aim to inspire the students to pursue careers in science and engineering. <br/><br/>A fundamental understanding of the reactions occurring at solid-solid interfaces is critical for the development of next-generation energy storage devices, such as lithium-oxygen batteries. Lithium-oxygen batteries have attracted significant interest in recent years due to their exceptionally high theoretical energy density. If even 15% of this energy density is achieved, then it would equal the value of gasoline, making lithium-oxygen batteries with driving ranges of up to 500 miles per charge commercially viable. While this technology is very attractive, numerous technical challenges need to be overcome before its widespread adoption is possible. Some of these challenges include: (i) insolubility of the solid discharge reaction products, leading to clogging of the cathode and eventually resulting battery cell death; (ii) low roundtrip (discharge-charge cycle) efficiency due to high charge overpotentials to dissociate the main discharge reaction product, lithium peroxide; and (iii) instability of electrolytes at high overpotentials. This research project seeks to alleviate these issues by designing solid-solid interfaces at the cathode of lithium-oxygen batteries that selectively stabilize lithium-deficient discharge products that are not insulating and can be dissociated at reasonable overpotentials. The researchers will apply a combined experimental and theoretical approach to study the chemistry at these solid-solid interfaces with the aim of designing materials that can selectivity tune the discharge product distribution such that it leads to improved battery performance. In particular, the work will involve a combination of advanced characterization studies and theoretical calculations to determine how the elemental composition, electronic properties, and symmetry of the oxide surface influence the discharge product distribution in lithium-oxygen cathodes. The studies will elucidate the effect of the global oxide crystal structure on the discharge product formation and lead to the development of design principles for identifying oxide electrocatalysts that are highly selective towards the formation of lithium-deficient oxide discharge products and therefore exhibit low charge overpotentials.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

AwardsFreedom CheteniSchool Administrators ResearchThe Superintendents Journal

Collaborative Research: Engineering the Chemistry at Solid-Solid Interfaces of Li-O2 Battery Cathodes: Wayne State University

Eranda Nikolla

[email protected]

Lithium-oxygen batteries potentially could have energy storage capacities that rival gasoline fuel, but there remains much fundamental scientific knowledge to learn about these batteries before the technology can be commercialized. In particular, some of the chemical products formed during the operation of the batteries can slowly degrade and poison the materials, leading to performance losses over extended periods of operation. This research project seeks to overcome these problems by exploring a class of inexpensive, mixed metal oxide electrocatalysts that may alter the chemistry of lithium-oxygen batteries. This project aims to develop a framework to engineer the chemistry of lithium-oxygen batteries, which are a potential next-generation energy storage device, and to improve their performance. The studies combine advanced characterization methods and theoretical calculations to determine how the properties of the oxide surfaces influence the products that are produced on lithium-oxygen electrodes. These insights will be leveraged to develop design principles that will aide in identifying oxide electrocatalysts that improve battery cell performance. The researchers involved in this project will partner with local K-12 schools to involve economically disadvantaged students with the proposed research through summer internships and student exchanges. They aim to inspire the students to pursue careers in science and engineering. <br/><br/>A fundamental understanding of the reactions occurring at solid-solid interfaces is critical for the development of next-generation energy storage devices, such as lithium-oxygen batteries. Lithium-oxygen batteries have attracted significant interest in recent years due to their exceptionally high theoretical energy density. If even 15% of this energy density is achieved, then it would equal the value of gasoline, making lithium-oxygen batteries with driving ranges of up to 500 miles per charge commercially viable. While this technology is very attractive, numerous technical challenges need to be overcome before its widespread adoption is possible. Some of these challenges include: (i) insolubility of the solid discharge reaction products, leading to clogging of the cathode and eventually resulting battery cell death; (ii) low roundtrip (discharge-charge cycle) efficiency due to high charge overpotentials to dissociate the main discharge reaction product, lithium peroxide; and (iii) instability of electrolytes at high overpotentials. This research project seeks to alleviate these issues by designing solid-solid interfaces at the cathode of lithium-oxygen batteries that selectively stabilize lithium-deficient discharge products that are not insulating and can be dissociated at reasonable overpotentials. The researchers will apply a combined experimental and theoretical approach to study the chemistry at these solid-solid interfaces with the aim of designing materials that can selectivity tune the discharge product distribution such that it leads to improved battery performance. In particular, the work will involve a combination of advanced characterization studies and theoretical calculations to determine how the elemental composition, electronic properties, and symmetry of the oxide surface influence the discharge product distribution in lithium-oxygen cathodes. The studies will elucidate the effect of the global oxide crystal structure on the discharge product formation and lead to the development of design principles for identifying oxide electrocatalysts that are highly selective towards the formation of lithium-deficient oxide discharge products and therefore exhibit low charge overpotentials.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

AwardsFreedom CheteniSchool Administrators ResearchThe Superintendents Journal

Engagement, Achievement, and Graduation of Undergraduate Students: A Partnership in STEM Education: Portland State University

Gwynn Johnson

[email protected]

This project will contribute to the national need for well-educated scientists, mathematicians, engineers, and technicians by supporting the retention and graduation of high-achieving, low-income students with demonstrated financial need at Portland State University and Heritage University. Portland State University is a four-year urban institution; Heritage University is a two-year, rural, minority-serving institution located on the Yakama Reservation in Washington State. Over its five-year duration, this project will bridge the urban-rural divide by awarding two-year or four-year scholarships to at least 116 students who are pursuing associate's or bachelor's degrees in STEM fields, including environmental sciences and engineering. The project is centered on the organizing theme of environmental pollution in the Columbia River Basin and the Pacific Northwest. Scholarships will be provided to high-achieving STEM students, enabling them to participate in research and service-learning projects that address authentic regional issues, focus on community-based challenges, and strengthen community connections. The project will create new STEM career pathways for Heritage University students by building a seamless transition into undergraduate STEM programs at Portland State University. Project outcomes include increased STEM retention and graduation rates of Scholars at both institutions. As a result, the project has the potential to broaden participation of traditionally underrepresented groups in the local and regional STEM workforce.<br/><br/>The overall goal of this project is to increase STEM degree completion of low-income, high-achieving undergraduates with demonstrated financial need. Through recruitment at local high schools and community colleges, outreach across both campuses, the use of promotional materials and social media postings, a broad group of Scholars will be recruited. The project will focus on increasing enrollment, retention, and graduation in STEM majors by developing the student's sense of science identity in environmental sciences and engineering. A research study will be conducted to advance understanding of correlative relationships between the many beneficial elements of the project, such as deliberative pedagogy, research experiences, student sense of community, science identity, and research self-efficacy. An experienced, independent external evaluator, who is an educational psychologist, will conduct formative and summative evaluation of the project. This project is funded by NSF's Scholarships in Science, Technology, Engineering, and Mathematics program, which seeks to increase the number of low-income academically talented students with demonstrated financial need who earn degrees in STEM fields. It also aims to improve the education of future STEM workers, and to generate knowledge about academic success, retention, transfer, graduation, and academic/career pathways of low-income students.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

AwardsFreedom CheteniSchool Administrators ResearchThe Superintendents Journal

Fate of Cadmium and Arsenic Under Engineered Physico-Chemical Gradients in the Soil-Water-Rice Nexus: University of Delaware

Angelia Seyfferth

[email protected]

Rice is a staple food for half the world's population. Despite its importance, the yield and quality of rice are threatened by arsenic and cadmium uptake from soil. Rice will uptake and concentrate arsenic when it is grown under conventional soil flooding, because arsenic is released into the water from biogeochemical reactions in the soil. This process can happen even when soil arsenic concentrations are low. Although minimizing soil flooding can decrease arsenic contamination of rice and even save water resources, doing so can increase rice grain uptake of cadmium from the soil. The goal of this research project is to develop methods that simultaneously limit rice uptake of both arsenic and cadmium. Manganese(II) is less toxic to plants than cadmium or arsenic and has been recently shown to share a root transport pathway with cadmium. Therefore, it should be possible to exploit the geochemical characteristics of manganese to decrease uptake of cadmium into the plant via engineered soil electrochemistry. This research project takes a multidisciplinary approach that incorporates geochemistry and plant biology methods and also will utilize resources at the NSF-funded Rice Investigation, Communication, and Education (RICE) Facility. This work will help train and foster the professional development of the next generation of STEM professionals to tackle the grand challenge of a sustainable food supply. Additional outreach efforts to high schools will increase scientific literacy of students and hopefully interest them in STEM careers.<br/><br/>Rice is often the first food consumed by infants and is also a staple food for half of the global population. However, the yield and quality of rice are threatened by the uptake of toxic arsenic and cadmium during the soil flooding process integral to rice cultivation. Although arsenic cycling has been well studied over the last two decades, cadmium cycling and uptake by rice is less well understood. The hypothesis behind this research project is that controlling manganese(II) availability can provide an engineered solution to limit cadmium and arsenic uptake by rice. The specific objectives of this project are 1) to understand the role of increasing manganese(II) availability in decreasing cadmium uptake by rice in simple hydroponic systems; 2) to evaluate the impact of engineered redox states on dissolution, plant uptake, and localization of metal(loid)s including manganese, iron, cadmium, and arsenic, in rice plants grown in rice paddy mesocosms; and 3) to compare traditional redox measurements to novel techniques for quantifying indicators of reduction in soil (IRIS) films. IRIS film technology will be evaluated as a low-cost means for farmers to know when to drain their fields in order to restrict rice uptake of toxic metalloids. The outcomes of this research will transform the ability of rice agronomists, wetland scientists, farmers, and other stakeholders to prevent toxic metal uptake and thereby safeguard the food supply of billions of people. The results of this study should be applicable to many other plants beyond rice, because many plants also accumulate cadmium.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

AwardsFreedom CheteniSchool Administrators ResearchThe Superintendents Journal

CAREER: New Probes of Heterogeneity in Next-Generation Nanocrystal Emitters: University of California-Los Angeles

Justin Caram

[email protected]

Professor Justin R. Caram of the University of California-Los Angeles is supported by the Macromolecular, Supramolecular, and Nanochemistry (MSN) Program and the Chemical Structure, Dynamics, and Mechanisms-A (CSDM-A) Program of the Division of Chemistry to develop new spectroscopic measurement methods to study the emission of short-wave infrared light from quantum dots. The quantum dots are incredibly small, man-made nanocrystals with diameters about 10,000 times narrower than a human hair. The research seeks to overcome the current limitations on instrumentation and methods at the single nanocrystal level. This goal is important because the nanocrystals come as an non-uniform mix of particles with different sizes, shapes and structures. This mixture complicates their study and hinders their use in optoelectronic devices. The knowledge obtained on single crystals may open the way for the systematic formation of uniform quantum dot materials with decreased toxicity and new functionality in the short-wave infrared — a spectral region beyond where human eyes can see. Success in conducting the research may widens the use of quantum dots in biomedical imaging, next-generation optoelectronic devices, optical communications, and solar energy conversion. During the course of this research, Professor Caram is revamping general chemistry courses through the development of learning laboratories that incorporate new pedagogical technologies to help students develop skills and motivation to continue their schooling in STEM majors after their first year in college. <br/> <br/>In this project, Professor Caram and his research team are supported to develop spectroscopic techniques to probe the intrinsic photo properties of short-wave infrared emitting (SWIR) colloidal nanocrystals, including HgX and CuInS2. The statistical variations from nanocrystal to nanocrystal and the average and distribution of exciton and mutilexciton lifetimes, yields and spectra of these nanoparticles in solution are assessed. SWIR photon-counting and correlation is achieved using recently developed spectroscopic tools. The project combines new infrared active detectors suitable for efficient photon counting, timing and correlation in shortwave infrared; path-length Mach-Zehnder interferometry to attain simultaneous temporal and spectral resolution, and fluorescence correlation spectroscopy to probe emitters as they diffuse through a focal volume in dilute solution. The research starts with a focus on HgX (X=S, Se, Te) quantum confined nanocrystals, which exhibit tunable bandgaps from 0 to 1.6 eV and have a wide range of applications in lasing, quantum communications, and infrared sensing. The focus shifts to the toxic cadmium-free nanostructure (CuInS2), which displays complex ensemble photoluminescence, including trap/defect emission, electrochemical doping and non-stoichiometry. The method employed resolves and correlates the energies of emitted photons as a function of inter-photon spacing, creating a two-dimensional map of emitter stream from dilute ensemble, in analogy to two-dimensional electronic spectroscopy.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

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