In this talk I will re-examine several key, assumed boundary conditions used in designing organic solar cells, and discuss novel device structures and thin film deposition techniques that can help circumvent a number of performance limiting factors. These include parasitic exciton quenching near electrodes, bulk recombination, and charge transport limitations.
Metallic nanoparticles support strong, localized oscillations of conduction electrons – surface plasmons – that have recently enabled significant improvements in photovoltaic and photocatalytic cell efficiencies. While considerable research has investigated the potential for somewhat larger plasmonic particles (>20 nm) to enhance solar energy conversion, most catalytic reactions rely on the high catalytic activity of very small metallic particles.
Despite the incredible market penetration of smartphones and exponential growth of the app market, utility of smartphones has been and will remain severely limited by the battery life. As such, energy has increasingly become the scarcest resource on smartphones which critically affects user experience. In this talk, I will start with a first study that characterizes smartphone energy bugs, or ebugs, broadly defined as an error in the smartphone system (apps, framework, OS, hardware) that results in unexpected smartphone battery drainage and leads to significant user frustration.
Power has become a first-class design constraint in computing platforms from the smartphone in your pocket to warehouse-scale computers in the cloud. Historically, semiconductor innovation has repeatedly provided more transistors (Moore’s Law) for roughly constant power per chip by scaling down supply voltage each generation. Unfortunately voltage scaling has ended due to stability limits and chip power densities are increasing each generation on a trajectory that outstrips improvements in the ability to dissipate heat.
Given the terawatt scale of future energy needs, the most promising future photovoltaic materials should be Earth abundant with their primary mineral resources distributed across several geographic regions and their supply chains robust to reduce concerns of price volatility. In addition, the process of forming the solar cell should be scalable, low-cost, and not utilize dangerous or toxic materials. The strongest initial candidate appears to be kesterite structures of Cu2ZnSnS4 (CZTS) and similar materials.
The ability of certain microorganisms to transfer electrons outside the cell has created opportunities for new types of energy generation including: microbial fuel cells (MFCs), to produce electrical power; microbial electrolysis cells (MECs), to produce fuels such as hydrogen and methane gases; microbial desalination cells (MDCs) to partially or fully desalinate water; and microbial reverse electrodialysis cells (MRCs) that can additionally be used to obtain salinity gradient energy. In an MFC, exoelectrogens oxidize organic matter and release electrons to the anode.
Academic papers have routinely reported power per bit numbers in the low pJs for several years. It may be reasonable to assume as an upper limit that deployed systems may achieve the one to two orders of magnitude improvement to reach 0.5 pJ/bit within the next 5 years. These optimistic electrical link estimates still fall short of energy performance required by advanced microprocessors. Here we demonstrate that the current state of photonic devices integrated in foundry CMOS foundry processes are competitive with existing and next generation on-chip power dissipation numb
Oracle Labs does industrial research in a broad set of areas of importance to the company. This seminar will give an overview of the Labs' projects, from silicon photonics and VLSI research to software areas like virtual machines and Domain-Specific Languages.
The development of high speed communications, interconnects and signal processing are critical for an information based economy. Lightwave technologies offer the promise of high bandwidth connectivity from component development that is manufacturable, cost effective, and electrically efficient. The concept of optical frequency/wavelength division multiplexing has revolutionized methods of optical communications, however the development of optical systems using 100’s of wavelengths present challenges for network planners.
Supplying the world with sustainable energy is one of the most pressing issues in modern society. Dramatically improved control over heat, electricity and solar energy is essential to create a new energy paradigm. Nanomaterials with carefully tailored properties (such as interface, geometry) can be used to manipulate the flow of phonons, electrons and photons, to enable novel energy devices in an unconventional manner. In this talk, I will present three examples of nanostructure-enabled energy devices.