ECCS-0801922 T. Huang, PA ST U University Park
Objective: The proposal focuses on developing a new class of ultra-small, all-optical plasmonic switches using photoactive rotaxanes as active components. The proposed photoactive rotaxane-based all-optical plasmonic switches could achieve unprecedented performance (size: molecular level; energy consumption: 1-2 eV; excellent reversibility and flexibility) and be integral components for the future ultra-small, ultra-fast plasmonic circuits and very large scale electronics and photonics integration (VLSEPI).
Intellectual merits: This project introduces light-driven molecular machines into optical device settings. Molecular machines driven by light have several advantages: they can be switched much faster; they do not produce any waste; light can be used for dual purposes¡Vinducing (writing) as well as detecting (reading) molecular motions. Experimental and numerical investigations will shed some light on the fundamental understanding of controlling plasmonics at molecular level. More importantly, with molecular machines¡¦ advantages in their size, energy consumption, speed, and controllability at molecular level, we expect that once established, the proposed rotaxane-based plasmonic switches will be welcomed in many applications such as optical communication.
Broader Impact: The PI will partner with the Penn State Center for Nanoscale Science and develop outreach activities around the theme of ¡¥from molecular shuttles to nanomechanics, nanoelectronics, and nanophotonics¡¦. A suite of demonstrations will imitate molecular machines¡¦ mechanical motions, broadly constructed and idealized in their operation by macroscopic models. The results developed in the past as well as from this proposal will be used to illustrate what molecular machines can achieve, and they will be delivered to museums, high-schools, and summer programs.
Project Summary: The proposal focuses on developing a new class of ultra-small, ultra-fast, all-optical plasmonic switches using light-driven molecular shuttles as active components. The specific molecular shuttles to be used are rotaxanes. Through this proposal, we have (1) manufactured a series of plasmonic nanostructures; (2) demonstrated Au nanodisk-based plasmonic switches using rotaxanes as active components; and 3) developed a mechanical actuator driven electrochemically by artificial molecular shuttles. The proposed rotaxane-based all-optical plasmonic switches could achieve unprecedented performance (size: molecular level; speed: THz range; energy consumption: 1-2 eV; excellent reversibility and flexibility) and be integral components for the future ultra-small, ultra-fast plasmonic circuits and very large scale electronics and photonics integration (VLSEPI). Intellectual Merit: Artificial molecular machines such as rotaxanes represent a highly promising and challenging field of interdisciplinary research. For example, the PI and colleagues have developed a rotaxane-based Nano-Electro-Mechanical-Systems (NEMS) - this work was selected by CAS Science Spotlight as "one of the five most intriguing articles in the third quarter of 2005" out of more than 200,000 journal articles. Recently, rotaxane-based ultra-dense molecular memory devices have been proven - the results were published in Nature (the January 25, 2007 issue) and highlighted by numerous US media including CNN, MSNBC, USA Today, New York Times, and NSF. Inspired by the recent success in molecular machine-based NEMS and molectronics, the proposed research is the first to apply light-driven molecular machines into device settings. Molecular machines driven by light have several advantages: they can be switched much faster; they do not produce any waste; light can be used for dual purposes–inducing (writing) as well as detecting (reading) molecular motions. The proposed research is also the first to explore molecular machines’ applications in plasmonics, a new branch of photonics that offers the opportunity to merge photonics and electronics at nanoscale dimensions. Our experimental and numerical investigations will shed some light on the fundamental understanding of controlling plasmonics at molecular level. More importantly, with molecular machines’ advantages in their size, energy consumption, speed, and controllability at molecular level, we expect that once established, the proposed rotaxane-based plasmonic switches will be welcomed in many applications such as optical communication. Broader Impact: In addition to addressing the technical matters, the PI has implemented vigorous education and outreach programs for a broader societal impact, which will be closely integrated with the proposed research and designed for groups at all levels. The concept of mechanical motion can be extrapolated across length scales from the molecular (sub-nanometer) level to the more familiar macroscopic world in which we live, so molecular machines provide an ideal topic for engaging the general public on nanoscience and technology. To obtain the broadest possible impact, the PI has partnered with the Penn State Center for Nanoscale Science (MRSEC), in which he is an active member, to develop and deliver outreach activities around the theme of ‘from molecular shuttles to nanomechanics, nanoelectronics, and nanophotonics’. The results developed in the past as well as from this proposal has been used to illustrate what molecular machines can achieve in three distinct fields (nanomechanics, nanoelectronics, and nanophotonics). Given the MRSEC’s established delivery channels through partnerships with museums (The Franklin Institute Science Museum in Philadelphia), high-schools (the State College School District), and summer programs (Action Potential Science Experience at Penn State), we has delivered this immersive, interactive experience in functional nanotechnology to the general public.
