To apply please fill out the application form, which includes:

• Background/identifying information
• Unofficial academic transcript
• Resume
• Two letters of recommendation from faculty
• Brief description (one or two paragraphs) of previous research experience and how this would relate to the Dartmouth REU program
• Brief description of how participating in the Dartmouth REU program will benefit your future academic and professional career
• Ranked list of research projects from the choices below

Dates & Deadlines (2023)

• March 1–31: Application window
• April 1–15: Notification of acceptance
• June 19–August 11: Tentative program dates; exact dates TBD

1. Understanding the origin of two-level systems in Al2O3 – Mattias Fitzpatrick
Modern quantum computers suffer from decoherence due to two-level systems (TLSs) in constituent materials. We aim to understand the true physical origin of these TLSs and in what portions of the circuit they reside. The student will grow Al2O3 films under the same growth conditions used in the fabrication of superconducting qubits and compare them to crystalline control films made using atomic layer deposition (ALD). Both sets of films will be characterized using atomic force microscopy (AFM), x-ray photoemission spectroscopy (XPS), and x-ray diffraction spectroscopy (XRD) to assess overall morphology, composition, and crystallinity.

2. Engineering the interface of sodium ceramic electrolytes for sodium metal batteries – Weiyang (Fiona) Li
Sodium-ion superionic conductors are one of the most promising sodium-ion conducting ceramic solid electrolytes owing to their high sodium-ion conductivity and excellent electrochemical and thermal stabilities. However, to date, there has been little success in the development of high-performance solid-state sodium batteries using this exceptional material. This project aims to address the interfacial challenges with ultrathin metal oxide materials by atomic layer deposition (ALD). A suite of characterization methods (including XRD, SEM, TEM, XPS) will be used to analyze materials' interfacial morphologies, microstructures, composition, and evolution.

3. Advanced medium entropy alloy (MEA) soft magnets – Ian Baker
The application of modern power electronics has the potential to reduce the world's energy consumption by 20%. However, current soft magnets do not have sufficient magnetic properties at temperatures >500 K to enable the full potential of applications in next-generation power electronics and various electrical machines. The aim of this project is to produce MEA soft magnets with a ~10-nm grain size which will significantly increase their range of applications. The student will produce nanograined bulk MEAs by mechanical alloying of elemental powders followed by backpressure-assisted equal channel angular extrusion. The phases present and the grain sizes will be determined by X-ray powder diffraction and the magnetic properties will be determined using a vibrating sample magnetometer.

4. Fabrication of conductive 3D-printed carbon materials – Chenfeng Ke
Additive manufacturing technology, aka 3D printing, can produce complicated structures rapidly without molds, and has demonstrated an ability to create artificial tissues, bionic ears, Li-ion microbatteries, chemical reactionwares, and ultra-stiff metamaterials promising future applications in daily life. The technology, however, is still in its infancy, and common 3D printing materials suffer from a lack of functionality at the molecular level. As a continuous effort, we are developing smart 3D-printed carbon-based materials. In this project, the student will use a direct ink-writing 3D printer and work on the assembly of 3D-printable polymers into ordered structures which will be calcinated into carbon materials while keeping the 3D-printed architecture.

5. Fabrication and property tuning of polymer-derived ceramics (PDCs) – Yan Li
The polymer-to-ceramic phase transition opens exciting opportunities to produce a broad spectrum of PDCs with tailored properties. This project aims at exploring the role of material composition, structure architecture, and key processing parameters on mechanical response of PDCs. Students will be trained for PDC sample preparation, CAD-based structure/architecture design, 3D printing, and mechanical property evaluation through compression tests and hardness tests. Students will also use scanning electron microscopy (SEM) to investigate the effect of heating rate and pyrolysis temperature on PDC microstructures.

6. Measurements of nonlinear dielectric behavior in MnZn Ferrites – Charles R. Sullivan
MnZn ferrites are the material of choice for magnetics in modern power electronics due to their low power losses, but aspects of the loss behavior are not well understood. Measurements show a more severe degradation of power handling capability at large sizes than would be expected based on the linear properties. We hypothesize that this is the result of nonlinear dielectric behavior. The student will set up a system to measure large-signal dielectric properties of MnZn ferrites with an amplifier to increase the excitation level. The system will test our hypothesis and the results could help predict power performance and improve the design of magnetic cores.

7. Ice growth on surfaces with variable material properties – Emily Asenath-Smith
Tragedies caused by icing are vast and widespread. Ice adhesion research is developing coatings to mitigate ice damage, but technology transfer to the field is slow. This stems from a need to understand not only how ice is removed from surfaces, but also how material properties affect the formation of ice on surfaces. We developed both a method to grow ice with well-defined microstructures on surfaces with variable material properties, and a new versatile testing approach. With these tools, the student will characterize surface material properties, grow ice on these surfaces, and study the micro-structure of the adhered ice.

8. Controlling the photophysical properties of liquid crystals using switchable dopants – Ivan Aprahamian
Adaptive liquid crystals (LCs) are used in a myriad of applications, from active smart surfaces to sensors, color filters, and responsive reflectors. Although chiral switchable dopants are at the heart of these applications, the nature of the interactions between them and the host LC is poorly understood. The student will synthesize new chiral dopants and chiral hydrazone switches using established protocols. The student will then use NMR and UV spectroscopies to characterize the compounds and study their switching properties. Next, the chiral switches will be doped in liquid crystals and their HTP and DHTP will be assessed using polarized optical microscopy.

9. Band engineering of 2D-conducting oxide semiconductors for flexible electronics – William Scheideler
2D metal oxides are an emerging class of transparent, ultra-thin materials that could enhance performance of wearable sensors and display technology. This work seeks to understand how alloyed liquid metals can control the formation of nanocrystalline vs. amorphous phases in 2D oxides while engineering their electronic structure and optical properties. Using the rapid liquid metal printing approach developed by our lab, the student will fabricate 2D oxide nanosheets and measure the materials' electronic and optical properties to be correlated with crystallinity through X-ray diffraction measurements. The student will also integrate these materials into thin-film transistors and measure switching characteristics to understand the impact of doping/alloyed channel materials.

10. High-efficiency, high-temperature solar selective absorber coatings ­– Jifeng Liu
Concentrated solar power (CSP) systems offer a method of low-cost solar thermal energy storage. A critical and challenging component is the solar absorber coating. This project investigates transition metal oxide nanoparticle (NP)-pigmented, high-temperature solar selective coatings for long-term applications at 750–800ºC in air. The student will learn solution-chemical synthesis of these NP pigments and the spray coating process, and will investigate the use of low thermal emittance matrix materials for improved thermal efficiency. They will also learn optical, crystal, and microstructure characterization to establish the structure-property relationship in these absorber coatings.