Major Research Themes:
Synthesis of metallic and semiconductor particles with dimensions below 100 nm has enabled control of materials properties ranging from color to magnetic moment. We have explored the fundamental limits to nanoparticle performance with particular emphasis on information technologies ranging from magnetic storage to high-throughout biological screening.
Three variable temperature instruments are used to probe the properties of metallic and semiconductor nanoparticles. These include a 9K scanning probe microscope with STM and AFM capabilities, a 2K microwave probe station, and a 4K optical spectroscopy cryostat.
- Chen, S. C., S. L. Lee, H. Lo, Y. J. Hung, K. Y. Lee, C. G. Tu, Y. T. Pan and R. J. Ram. “Silicon Platform with Vertically Aligned Carbon Nanotubes for Enhancing Thermal Conduction in Hybrid Optoelectronic Integration.” IEEE Trans. Compon. Packag. Manuf. Technol. 2.7 (2012): 1128-34. [PDF]
- Bahk, Je-Hyeong, Parthiban Santhanam, Zhixi Bian, Rajeev Ram, and Ali Shakouri. “Resonant Carrier Scattering by Core-Shell Nanoparticles for Thermoelectric Power Factor Enhancement.” Applied Physics Letters 100 (2012). [PDF]
- Bahk, J., Z. Bian, M. Zebarjadi, P. Santhanam, R. J. Ram, and A. Shakouri. “Thermoelectric Power Factor Enhancement by Ionized Nanoparticle Scattering.” Applied Physics Letters 99 (2011). [PDF]
- Liptay, T. J., L. F. Marshall, P. S. Rao, R. J. Ram, and M. G. Bawendi. “Anomalous Stokes Shift in CdSe Nanocrystals.”
Physical Review B 76 (2007): 155314. [PDF]
- Liptay, T., and R. J. Ram. “Temperature Dependence of the Exciton Transition in Semiconductor Quantum Dots.” Applied Physics Letters 89 (2006): 223132. [PDF]
- Schmidt, H., and R. J. Ram. “Coherent Magnetization Reversal of Nanoparticles with Crystal and Shape Anisotropy.” Journal of Applied Physics 89.1 (2001): 507-13. [PDF]
- Abraham, M. C., H. Schmidt, T. A. Savas, C. A. Ross, H. I. Smith, and R. J. Ram. “Magnetic Properties and Interactions of Single-Domain Nanomagnets in a Periodic Array.” Journal of Applied Physics 89.10 (2001): 5667-70. [PDF]
- Hwang, M., M. C. Abraham, T. A. Savas, H. I. Smith, R. J. Ram, and C. A. Ross. “Magnetic Force Microscopy Study of Interactions in 100 nm Period Nanomagnet Arrays.” Journal of Applied Physics 87.9 (2000): 5108-10. [PDF]
- Ross, C. A., H. I. Smith, T. Savas, M. Schattenburg, M. Farhoud, M. Hwang, M. Walsh, M. C. Abraham, and R. J. Ram. “Fabrication of Patterned Media for High Density Magnetic Storage.” J. Vac. Sci. Technol. B 17.6 (1999): 3168-76. [PDF]
- S. Chen, S. Lee, H. Lo, Y. Hung, K. Lee, C. Tu, Y. Pan, R. J. Ram, "Silicon Platform with Vertically Aligned Carbon Nanotubes for Enhancing Thermal Conduction in Hybrid Optoelectronic Integration," IEEE Trans. Compon. Packag. Manuf. Technol. 2.7 (2012): 1128-34, [PDF]
- J. Bahk, P. Santhanam, Z. Bian, R. J. Ram, A. Shakouri, "Resonant Carrier Scattering by Core-Shell Nanoparticles for Thermoelectric Power Factor Enhancement," Applied Physics Letters 100 (2012) DOI: 10.1063/1.3673615 [PDF]