Bulletin of the American Physical Society
2005 APS March Meeting
Monday–Friday, March 21–25, 2005; Los Angeles, CA
Session X14: Nanomechanical Physics and Devices |
Hide Abstracts |
Sponsoring Units: FIAP Chair: Rajiv Kalia, University of Southern California Room: LACC 403B |
Friday, March 25, 2005 8:00AM - 8:12AM |
X14.00001: Automatic Atomic/Molecular Assembly and Atom Sound Timur Skeini, Kai-Felix Braun, Saw-Wai Hla We report the development of an automation scheme for single atom/molecule assembly on metallic surfaces using scanning tunneling microscope (STM) tip. Our real time computer control scheme automatically identifies the type of objects (atoms/molecules) to be moved, calculates the STM-tip movement path by avoiding obstacles such as steps/defects and then actually moves the atom/molecule to the desired locations on the surface to form engineered patterns using STM lateral manipulation technique (1,2,3). During the manipulation process, the STM tip-height is initially reduced above the atom/molecule in order to increase the tip-atom/molecule interactions, and then the tip is moved along a computed path across the surface. The atom/molecule moves in a discontinuous manner by hopping between the surface sites. Moreover, the atom/molecule sounds can be generated from the manipulation signals, which further reveal the dynamics of atom/molecule movements during the manipulation processes. (1). S.-W. Hla, K.-F. Braun, V. Iancu, A. Deshpande, Nano Lett. 4 (2004) 1997-2001. (2). S.-W. Hla, K.-F. Braun, K.-H. Rieder, Phys. Rev. B 67 (2003) 201402(R). (3). J.A. Stroscio and R.J. Celotta, unpublished work. This work is financially supported by the NSF-NIRT grant no. DMR- 0304314 and the US-DOE grant no. DE-FG02-02ER46012. [Preview Abstract] |
Friday, March 25, 2005 8:12AM - 8:24AM |
X14.00002: Atomic force microscopy electrostatic nanolithography on self-assembled monolayer of organo-mercaptan molecules Michael A. Reagan, Olga V. Mayevska, Pavel B. Paramonov, Sergei F. Lyuksyutov, Shane Juhl, Richard A. Vaia, Kazuo Umemura We report a \textit{novel} technique for manipulating SAM molecules at the nanoscale. An initial stage, the AFM probe induces local modification of the self-assembled monolayer involving cleavage of the sulfur-metal bond. This leads to depressions appearing on the surface's topography images followed by the removal (diffusion) of the desorbed specie. It is known from the macroscopic scale electrochemical experiments that oxidative desorption of the organo-mercaptans from the gold surface takes place at potentials greater than +0.8 V (vs. Ag/AgCl) in aqueous KOH solutions. This corresponds to about -3.9 V in the absolute potential scale. A weak positive bias of the metal substrate is expected to result in the dissociative electron transfer from the mercaptan to the gold, taking place in the surface region localized near the scanning probe tip, where the water can be condensed from the ambient environment forming a nanoscale electrochemical cell. [Preview Abstract] |
Friday, March 25, 2005 8:24AM - 8:36AM |
X14.00003: Quantum Dissipation in Nanomechanical Structures at Millikelvin Temperatures Guiti Zolfagharkhani, Alexei Gaidarzhy, Seung-Bo Shim, Pritiraj Mohanty We report measurement of dissipation (inverse quality factor) and resonance frequency shift in a series of nanomechanical resonators with megahertz-range resonance frequencies. These structures are fabricated from single-crystal silicon by electron-beam lithography and surface nanomachining. The measurements are done at down to a temperature of 60 millikelvin. The temperature dependencies show reproducible features, which indicate the coupling between acoustic phonons and surface and bulk two-level systems as the dominant mechanism of dissipation. We compare the data to a model of quantum dissipation in the Caldeira-Leggett model. This work is supported by the NSF (DMR, CCF, ECS), DOD (ARL), ACS (PRF) and the Sloan Foundation. [Preview Abstract] |
Friday, March 25, 2005 8:36AM - 8:48AM |
X14.00004: Nanomanipulation using only mechanical energy Ivan Stich, Peter Dieska, Ruben Perez We present the first computational study targeting the capability of dynamic surface force microscopy as a key tool for performing surface nanomanipulation, a possibility recently demonstrated also experimentally [1]. Using a very simple realistic model, an antisite defect on a III- V (110) surface, we show how the defect can be manipulated using exclusively mechanical energy of the oscillating tip. The atomistic details are elucidated and discussed in the context of the related experiments. Simultaneously, the study sheds light also on other key issues, such as chemical resolution and atomic resolution based on dissipation contrast formation. [1] N. Oyabu, et al., Phys. Rev. Lett. {\bf 90}, 176102 (2003). [Preview Abstract] |
Friday, March 25, 2005 8:48AM - 9:00AM |
X14.00005: Fabrication and Characterization of Free-Standing Silicon Nano-Meshes M. E. Curtis, P. R. Larson, J. C. Keay, M. Keil, X. Wang, M. Xiao, M. B. Johnson Free-standing nanometer-sized silicon meshes have been fabricated on silicon-on-insulator substrates using a combination of photolithography, wet-anisotropic etching, porous alumina templates, and dry etching techniques. The resulting structure consists of an array of holes with 50 nm diameters and 100 nm spacings. Such nano-meshes will be useful for nano-filtration and sensor array applications. These silicon structures can be further reduced in size by various techniques. For example, self-limiting oxidation on similar structures leaves behind Si cores with sub- 5 nm dimensions encased in silicon oxide. The photoluminescence from such structures indicate quantum confinement effects. The results for photoluminescence and absorption spectroscopy measurements on these free-standing meshes will be discussed. This work was supported by NSF grant nos. ECS-9734228, DMR-0080054, and NSF-0132534. [Preview Abstract] |
Friday, March 25, 2005 9:00AM - 9:12AM |
X14.00006: Screw-Joints and Symmetries: Designing Nucleic Acid Nanotubes as Nano-Machines William Sherman, Nadrian Seeman In 2001, Mathieu \textit{et al.}$^{1}$ presented the first nanotube constructed from DNA. Similar experimental techniques can be used to build a variety of other DNA nanotubes, but finding solutions to the structural constraint equations can be difficult. We show how symmetry based analysis can be used not only to find viable tube structures, but also to identify tube based devices. Such devices can pass through several states with varying tube profiles, inner and outer radii, and lengths. The theoretical basis for actuation of the devices is the screw-joint -- two double-helical domains joined by two or more symmetric Holliday junctions and one (or more) immobile Holliday junction(s). Two of the strands in the immobile junction can be pulled out of the system and replaced with different strands. This process changes the state of the device in a controlled and reversible manner. These devices are promising as gated pores, as well as stiff mechanical manipulators. This research supported by NIGMS, ONR, and NSF. $^{1}$ F. Mathieu, C. Mao, N. C. Seeman, \textit{Journal of Biomolecular Structure {\&} Dynamics}, \textbf{18}, p.907 (2001). [Preview Abstract] |
Friday, March 25, 2005 9:12AM - 9:24AM |
X14.00007: Fundamental Issues of Single Molecule Manipulation: Driving Nanotrucks Andrew Osgood, Yasuhiro Shirai, Yuming Zao, J. M. Tour, K. F. Kelly The current trend in the physical and biological sciences is the continued miniaturization of machinery from the macroscopic to the microscopic world. The ultimate goal is to build machines at the nanoscopic level from individual molecules. However, this bottom-up approach presents a critical question of how to control the molecular-sized machines. We have synthesized the molecular nanoscale vehicle NanoTruck, and seek to control the NanoTruck using a STM. The NanoTruck is similar to a macroscopic truck by integrating three essential components, a planar ``chassis," four rotating ``axles," and four round ``wheels." Our work has consisted of characterizing and manipulating these molecules and other similar derivatives with STM in both UHV and ambient conditions at room temperature and above. Results from these experiments are discussed. [Preview Abstract] |
Friday, March 25, 2005 9:24AM - 9:36AM |
X14.00008: Nanocrystal Powered Nanomotor B.C. Regan, S. Aloni, K. Jensen, R.O. Ritchie, A. Zettl We have constructed and operated a nanoscale linear motor, powered by a single metal nanocrystal ram sandwiched between mechanical lever arms. Low-level electrical voltages applied to the carbon nanotube lever arms grow or shrink the nanocrystal, virtually atom-by-atom, in a controlled manner. The thermodynamic principles governing the motor operation resemble those driving frost heave, a natural solid-state linear motor. [Preview Abstract] |
Friday, March 25, 2005 9:36AM - 9:48AM |
X14.00009: Quantum Method for Fault Tolerance Calculations in Quantum-dot Cellular Automata Clocked Devices Ioan Sturzu, Mahfuza Khatun A full basis quantum method is used for the study of the joint influence of temperature and positional defects on quasi-adiabatically clocked Quantum-dot Cellular Automata (QCA) devices. The full quantum statistical calculation is done diachronically at the level of a clocking zone in the locking phase, while the charge distribution of the other clocking zones is considered as external conditions. A full basis quantum method requires numerical calculations with large sparse matrices. Therefore, usage of some approximation techniques is needed for larger clocking zones. Using an approximation method results for thermal effect and fabrication defect properties will be shown for a wire and a shift register. The work has been supported by the Indiana 21$^{st}$ Century Research and Technology Fund ({\#}04-492) [Preview Abstract] |
Friday, March 25, 2005 9:48AM - 10:00AM |
X14.00010: Defect Tolerance Properties Cal\-cu\-lations for Quan\-tum-dot Cellular Auto\-mata using Inter\--cellular Hartree Approximation Travis Barclay, Ioan Sturzu, Mahfuza Khatun A numerical study of the fabrication defects influence on Quantum-dot Cellular Automata (QCA) operation is presented. The statistical model that has been introduced simulates the random distribution of positional defects of the dots within cells, and of cells within arrays. We have studied specific non-clocked QCA devices using Inter-cellular Hartree Approximation, for different temperatures. Parameters such as success rate and breakdown displacement factor were defined and calculated numerically. Results show the thermal dependence of breakdown displacement factor of the QCA devices. The breakdown displacement factor decreases with the temperature. The work has been supported by the Indiana 21$^{st}$ Century Research and Technology Fund ({\#} 04-492) [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