Dr. Hahn is a US patent agent registered with the USPTO with expertise in patent prosecution and strategic patenting. He has been a scientist and inventor for more than 20 years. His experience covers a wide range of science and technology, including physics, chemistry, materials, biochemistry, and scientific equipment. He has been a full professor of chemistry at Chonbuk National University and recently served as the head of the department. He has also served as an Adjunct Professor at North Carolina State University since 2013, and previously worked as a research scientist at Cornell University, the University of California (Irvine) and Seoul National University (Korea). Dr. Hahn has published more than 100 research papers in the Peer Review Journal. His research includes surface physics and chemistry, semiconductor devices, molecular electronics, nanotechnology, advanced organic and inorganic materials, energy storage materials and biosensors. In particular, he received a Young Vacuum Scientist Award in vacuum science and a Young Researcher Assistance program.
Dr. Hahn is active in the field of intellectual property. He is a founder of a consulting company (Hahn & Nation IP) for the filing of US patent applications and is working as a US patent agent registered with the US Patent and Trademark Office. In addition, Dr. Hahn has actively participated in the examination and evaluation of the Korean patent agents' qualifications in Korea.
M. M. Hossain, H. Shima, B.-C. Ku, J. R. Hahn, “Nanoforests composed of zinc oxide/carbon core-shell hexagonal nanosheets: fabrication and growth in a sealed thermolysis reactor and optical properties”, J. Mater. Sci. 50, 93-103 (2015).
A. H. A. Mamun, S. Yoon, J. R. Hahn, “Influence of the molecular-scale structures of 1-dodecanethiol and 4-methylbenzenethiol self-assembled monolayers on gold nanoparticles adsorption pattern”, J. Colloid Interface Sci. 425, 83-90 (2014).
J. R. Hahn, S. C. Bharath, G. -H. Kim, K. W. Kim, S. Jeong, T. P. Pearl, “Adsorption site selectivity for thiophene on reconstructed Si(5 5 12)–2×1 surface”, J. Phys. Chem. C 117 (21), 11197-11202 (2013).
A. H. A. Mamun, J. R. Hahn, „Effects of solvent on the formation of octanethiol self-assembled monolayers on Au(111) at high temperatures in a sealed bath: a scanning tunneling microscopy and X-ray photoelectron spectroscopy study”, J. Phys. Chem. C 116(42), 22441-22448 (2012).
M. M. Hossain, A. H. A. Mamun, J. R. Hahn, Fabrication of solid cylindrical shaped microtowers of ZnO/C core-shell hexagonal nanorods by thermolysis, J. Phys. Chem. C 116(43), 23153-23159 (2012).
J. R. Hahn, S. C. Bharath, S. Jeong, T. P. Pearl, “Binding structures of propylene glycol stereoisomers on the Si(001)-2x1 surface: A combined scanning tunneling microscopy and theoretical study”, J. Chem. Phys. 134, 044704 (2011).
J. R. Hahn, S. H. Jang, S. Jeong, “Pairing of (R,R)-2,3-butanediol molecules on a Si(001) surface”, J. Phys. Chem. C 114 (41), 17761-17767 (2010).
J. R. Hahn, W. Ho, “Spatially inhomogeneous inelastic electron tunneling in oxygen-ethylene complexes on Ag(110) resolved with a scanning tunneling microscope”, Phys. Rev. B 80 (14), 165428 (2009).
J. Q. Hou, H. S. Kang, K. W. Kim, J. R. Hahn, ”Binding characteristics of pyridine on Ag(110) surface”, J. Chem. Phys. 118, 134707 (2008).
S. H. Jang, S. Jeong, J. R. Hahn, ”Adsorption structures of 2,3-butanediol on Si(001)”, J. Phys. Chem. C 111, 340-344 (2007).
H. Jeong, S. Jeong, S. H. Jang, J. M. Seo, J. R. Hahn, ”Atomic structures of benzene and pyridine on Si(5 5 12)”, J. Phys. Chem. B 110 (32), 15912-15919 (2006).
J. R. Hahn, W. Ho, “Imaging and vibrational spectroscopy of single pyridine molecules on Ag(110) using a low-temperature scanning tunneling microscope”, J. Chem. Phys. 124, 204708 (2006).
J. R. Hahn, H. Jeong, S. Jeong, ”Adsorption structures of benzene on a Si(5 5 12)-2x1 surface: A combined STM and theoretical study”, J. Chem. Phys. 123 (24) 244702 (2005).
J. R. Hahn, W. Ho, “Orbital specific chemistry: Controlling the pathway in single-molecule dissociation”, J. Chem. Phys. 122, 244704 (2005).
J. R. Hahn, “Kinetic study of graphite oxidation along two lattice directions”, Carbon 43, 1506-1511 (2005).
J. R. Hahn, H. Kang, “Local and non-local functions of Cs promoter in the O2-oxidation of graphite”, J. Phys. Chem. B 106 (30), 7445-7448 (2002).
J. R. Hahn, W. Ho, “Oxidation of a single carbon monoxide molecule manipulated and induced with a scanning tunneling microscope”, Phys. Rev. Lett. 87 (16), 166102 (2001). This paper was introduced in four significant scientific media: [Physics Update News, AIP], [News of the Week, C&EN News, ACS], [News and Views, Nature], and [Research and Researchers, MRS Bulletin].
J. R. Hahn, H. J. Lee, W. Ho, “Electronic resonance and symmetry in single-molecule inelastic electron tunneling”, Phys. Rev. Lett. 85 (9), 1914-1917 (2000).
S. M. Lee, Y. H. Lee, Y. H. Hwang, J. R. Hahn, H. Kang, “Defect-induced oxidation of graphite”, Phys. Rev. Lett. 82, 217-220 (1999).
J. R. Hahn, H. Kang, “Vacancy and interstitial defects at graphite surfaces. scanning tunneling microscopic study of the structure, electronic property, and yield for ion-induced defect creation”, Phys. Rev. B 60, 6007-6017 (1999).
J. R. Hahn, H. Kang, S. Song, I. C. Jeon, “Observation of charge enhancement induced by graphite atomic vacancy. A comparative STM and AFM study”, Phys. Rev. B 53 (4), R1725-R1728 (1996).