Bulletin of the American Physical Society
2016 Annual Meeting of the APS Mid-Atlantic Section
Volume 61, Number 16
Saturday–Sunday, October 15–16, 2016; Newark, Delaware
Session C2: Quantum Dots, Photonics, and Solar Cells |
Hide Abstracts |
Chair: Frank Abel, University of Delaware Room: Sharp Laboratory 130 |
Saturday, October 15, 2016 2:00PM - 2:36PM |
C2.00001: Controlling light on the nanoscale: Colloidal quantum-well lasers and strong plasmon -- quantum dot coupling Invited Speaker: Matthew Pelton My research focuses on the dynamical processes that occur when light interacts with semiconductor nanocrystals, metal nanoparticles, and assemblies of these particles. The interaction between light and these nanoparticles depends on their size and shape, enabling a wide range of new and emerging applications. Enabling these applications will require an understanding of the processes by which the particles convert incident optical energy into other forms of energy, and how these processes relate to nanoscale structure. I will discuss two of my recent attempts to understand and take advantage some of these processes in order to enable future optical information processing: (1) Flat, thin semiconductor nanocrystals, or nanoplatelets, can be used to construct lasers with record low thresholds. (2) Coherent coupling of plasmonic metal nanoparticles has the potential to enable optical modulation on the nanoscale, at high speeds, and with low power consumption. [Preview Abstract] |
Saturday, October 15, 2016 2:36PM - 2:48PM |
C2.00002: Room-temperature composite transparent electrodes for solution-processed solar cells Gary Qian Colloidal quantum dots (CQDs) are promising materials for semi-transparent solar cells due to their infrared responsivity and ability to be flexibly coated on a variety of substrates. One limiting factor in the creation of high-performing semi-transparent CQD solar cells is the top transparent contact. Existing contact materials include indium tin oxide (ITO), which suffers from fragility, cost, and manufacturing difficulties; specifically, the ability to be processed at the low temperatures compatible with the underlying CQD films. Solution-processed silver nanowires (AgNWs) are a possible alternative but have not achieved the conductivity of the best-performing transparent conductors to date. We develop a novel, room-temperature, all-solution-processed transparent conductor composed of AgNWs and colloidal ITO nanoparticles with conductivity rivaling the best high temperature alternatives. We discuss characterization results and the integration of our new top contact into a CQD solar cell device. [Preview Abstract] |
Saturday, October 15, 2016 2:48PM - 3:00PM |
C2.00003: Charge transfer and polaron states in bulk heterojunction solar cells Marian Tzolov, Max McIntyre The absorption mechanisms in bulk heterojunction solar cells have been studied using Fourier Transform Photocurrent Spectroscopy and Electroabsorption Spectroscopy. Device structures have been fabricated by sandwiching the active films between transparent conductive (ITO) and aluminum electrodes. The active films have been spin coated using 3 types of polymers, P3HT, PCDTBT, and PCPDTBT, and PC60BM. For comparison, structures containing polymer films w/o PCBM have been prepared and studied. The presence of PCBM is known to enhance dramatically the photocurrent generation. Our measurements reveal that dramatic changes appear also in the subgap photocurrent and electroabsorption. We identify a characteristic feature just below the absorption edge as charge transfer state in agreement with previous reports. The polaron states have been identified in the electroabsorption spectra at energies coinciding with the maximum of the absorption spectrum. Impedance spectroscopy data support further this hypothesis. These results contribute to the differentiation between the charge transfer and polaron states in bulk-heterojunction structures. [Preview Abstract] |
Saturday, October 15, 2016 3:00PM - 3:12PM |
C2.00004: Flexible Integrated Concentrator Lenses for Colloidal Quantum Dot Solar Cells Garrett Ung, Gary Qian, Yida Lin, Susanna M. Thon Colloidal quantum dot (CQD) solar cell research is a growing field due to the solution processability and band gap tunability of CQD materials. However, most device performance results reported to date have come from very small-area solar cell demonstrations due to the difficulty in fabricating uniform large-area CQD films. We will discuss a method for the fabrication of low-cost integrated concentrator lenses for CQD solar cells made from polydimethylsiloxane (PDMS). The concentrators allow a larger area of sunlight to be collected by a smaller area CQD solar cell, offering the benefits of a large-area cell while maintaining low material utilization and high efficiency. The lens fabrication process utilizes a 3D-printed acrylonitrile butadiene styrene (ABS) mold to allow for inexpensive creation of the lens. We will discuss optimal shapes and treatments for the mold used to improve lens quality, optical modeling of the lens system, and device performance results. [Preview Abstract] |
Saturday, October 15, 2016 3:12PM - 3:24PM |
C2.00005: Flexible and Broadband Photodetectors via Solution Processed Antimony Selenide Ebuka Arinze, Md Rezaul Hasan, Arunima Singh, Vladimir Oleshko, Shiqi Quo, Asha Rani, Irina Kalish, Yan Cheng, Mona Zaghloul, Mulpuri Rao, Nhan Nguyen, Abhishek Motayed, Albert Davydov, Ratan Debnath, Susanna Thon The demand for high-performing low-cost broadband photon detection has generated interest in new materials that couple high absorption with traditional electronic infrastructure (CMOS) compatibility. In this study, we demonstrate a facile, low-cost and scalable, catalyst-free one-step solution-processed approach to grow one-dimensional Sb$_{\mathrm{2}}$Se$_{\mathrm{3}}$ nanostructures directly on flexible substrates for high-performing near infrared (NIR) photodetectors. Structural characterization and compositional analyses reveal high-quality single-crystalline nanowires with orthorhombic crystal structure and a near-stoichiometric atomic ratio of antimony to selenium (Sb: Se). A measured direct band gap of 1.12 eV is consistent with predictions from theoretical simulations, indicating strong NIR potential. Metal-semiconductor-metal photodetectors fabricated from this material exhibit fast response (on the order of milliseconds), high performance (responsivity \textasciitilde 0.27 A/W), outstanding mechanical flexibility, and structural durability. The experimental results demonstrate the potential of solution-processed Sb$_{\mathrm{2}}$Se$_{\mathrm{3}}$ nanostructures in flexible and broadband optoelectronic devices. [Preview Abstract] |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700