Devices and Circuit Design Strategies for Building Scalable Integrated Molecular Circuits

Lebeck, Alvin R

LaBoda, Craig

2017-05-16T17:28:08Z

2017-10-26T04:30:05Z

2017

Electrical and Computer Engineering

Resonance energy transfer (RET) logic provides a method for building integrated molecular circuits using self-assembled networks of fluorescent molecules to perform computation. The unique operating principles and materials of these circuits make them suitable candidates for introducing computation to domains that are incompatible with conventional silicon-based systems. To realize the full potential of this technology, however, a variety of technical challenges currently preventing the design of larger, more complex systems must be overcome. Two of these primary challenges are energy loss and exciton loss. Energy loss forces the outputs from RET devices to be red-shifted from their inputs. This prevents most independently designed RET components from being cascaded with one another. Exciton loss weakens the output signals from RET devices, making it difficult to observe the computational results. Together, these forms of signal degradation constrain both the size and topology of RET systems.

This work explores new RET devices and circuit design strategies that address the above limitations. The primary contributions of this dissertation are threefold. First, a RET device capable of restoring energy in these systems is designed and experimentally demonstrated. This device enables cascading and feedback in RET logic, two circuit design concepts commonly used in large-scale digital systems. Second, a new style of RET logic design, called Pre-Charge Logic (PCL), is introduced. PCL addresses both forms of signal loss while simultaneously providing a library of cascadable RET logic gates, many of which cannot be implemented using previous methods of RET logic design. Third, the design methods of PCL are explored and validated by simulation and experimental demonstration. Continuous-time Markov chain modeling confirms that the proposed PCL devices perform their intended Boolean operations, while an experimental demonstration of a PCL PASS gate substantiates the underlying operating principles of these devices. Collectively, these contributions pave the way for developing larger, more complex RET systems in the future.

https://hdl.handle.net/10161/14456

Computer engineering

Dark States

Excitons

Fluorescence

Logic Gates

Resonance energy transfer

Upconverting Nanoparticles

Devices and Circuit Design Strategies for Building Scalable Integrated Molecular Circuits

Dissertation

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