SINETH PREMARATHNA
PhD Student
Athens,OH
Summary
Motivated Graduate Student Researcher with 5+ years of hands-on experience collecting spectroscopy and STM imaging on samples, calibrating and setting up STM, SX-STM, UHV equipment and presenting and preparing research reports. Reliable and diligent individual with proficiency in Python/MATLAB/C++/MS office. Comfortable collaborating with cross-functional research teams. In-depth knowledge of UHV equipment operations. Applies analysis, lean methodology and latest technology to lead change and tackle new projects and ideas. Enthusiastic team worker eager to contribute to team success through hard work, attention to detail and excellent organizational skills. Motivated to learn, grow and excel in process engineering roles.
Overview
8
8
years of professional experience
12
12
years of post-secondary education
Work History
Student Research Associate
Argonne National Laboratory
Woodridge, IL
06.2021 - Current
- Captured first ever X-ray signature of an individual atom using Synchrotron X-ray Scanning Tunneling Microscope (SX-STM) on Tb caged ligand molecules
- Obtained first ever X-ray STM image showing Tb and Eu caged ligand molecules highlighting their atomic positions
- Fabricated flower shaped self-assembled monolayers of Rare Earth (RE) caged ligands by thermally evaporating and annealing precursor molecules on to gold substrate
- Obtained, analyzed 2D spectroscopic maps of self-assembled structures and electronic signatures on individual RE caged molecules at various energies
- Transferred samples between different STMs using Ultra High Vacuum (UHV) suitcase
- Maintained Liquid Helium (LHe, 4K) and Liquid Nitrogen (LN2, 80K) cryogenic temperatures in SX-STM by refilling as needed
- Gathered, arranged and corrected research data to create representative graphs and charts highlighting results for presentations.
- Hands on experience at the World's first SX-STM dedicated beam line at Advanced Photon Source (APS)
Graduate Student Researcher
Ohio University
Athens, OH
05.2017 - Current
- Operated Ohio University Nanocar which was deposited in Ohio STM remotely from Toulouse France at World's 2nd Nanocar race and drove it for 136nm using STM tip electric pulses
- Created self assembled monolayers as well as clusters of Rare Earth (RE) caged molecular ligands on gold single crystals and discovered differences in structural and electronic properties amongst them
- Fabricated vertical and lateral Sexiphenyl (6P) - Armchair Graphene Nano Ribbon (AGNR) heterostructures on gold single crystals and achieved electronically decoupled 6P molecules from gold substrate on vertical heterostructures
- Demonstrated usability of Eu caged ligands as molecular machines by achieving controlled rotations using STM tip pulses on Au(111) and assessed threshold electric field needed for rotational events
- Chemically etched STM tips with tungsten wires and apex quality was assured by means of Scanning Electron Microscopy (SEM) Imaging
- Invented a novel STM tip conditioning setup to re-etch apexes of bent STM tips
- Increased LHe retention time of STM by 90% by rewiring STM connections rerouting through outside of inner cryostat
- Repaired Ultra High Vacuum (UHV) pressure gauge filaments by spot welding tungsten wires
- Maintained Liquid Helium (LHe, 4K) and Liquid Nitrogen (LN2, 80K) cryogenic temperatures in STM by refilling as needed
- Boosted UHV conditions of STM chamber by cleaning interior of ion pumps and replacing Titanium Sublimation Pump (TSP) filaments
- Used Python to perform qualitative and quantitative analysis of STM spectroscopy data.
- Increased molecular deposition coverage by utilizing a redesigned sample source that can approach substrate much closer in UHV
- Established heating and cooling curves of button heater attached custom built STM sample assembly in UHV conditions
- Procured UHV and other components for STM while working closely with university procurement specialists
- Mentored junior graduate students on UHV systems, material characterization, data acquisition and analysis techniques
Undergraduate Student Researcher
University Of Colombo, Sri Lanka
01.2014 - 02.2015
- Proposed a 2D cylindrical acoustic metamaterial cloak using FDTD methods using MATLAB® for both isotropic and anisotropic metamaterials.
Education
Doctor of Philosophy - Physics
Ohio University
Athens, OH 08.2016 - Current
Master of Science - Physics
Ohio University
Athens, OH 08.2017 - 08.2018
Bachelor of Science (Honors) - Physics
University of Colombo
Colombo, Sri Lanka 08.2010 - 01.2015
Skills
Operation, maintenance, design of experiments, procurement and troubleshooting of UHV systems, Ion pumps, turbo pumps, roughing pumps, TSP, DC sputter guns, DC annealing systems, Laminar flow isolators, effusion cells, cryogenic systems (5 years)
Python, Origin (5 years) MATLAB, C, MS Office, LaTeX, Mathematica, LabView, Statistica , SQL (10 years)
Problem Solving, Research program planning, Process Control Systems, Good Laboratory Practices (5 years)
Expertise in STM,SEM,AFM,SX-STM,EDS,XRD,SXAS,Optical Microscope,Oscilloscope (5 years)
Data collection, organization and Analysis (5 years)
Advanced synthesis and characterization (5 years)
Extensive experience in UHV soldering, spot-welding, chemical/wet etching and handling chemicals such as NaOH, IPA and acetone (5 years)
Expertise in spectroscopic mapping, molecular electronic and magnetic properties, self-assembled monolayers, molecular clusters, XAS on molecules, molecular vibrations, molecular machines, single crystals (5 years)
Expertise in deposition techniques such as thermal evaporation, drop casting, DC sputtering (5 years)
Excellent Team Work and Leadership Skills
Accomplishments
- Achieved 7th Place in World Nanocar race two held in Toulouse France representing Ohio University (Mar 2022)
- Awarded a fellowship from Department of Physics, Ohio University funded by Department of Energy Office of Science, Basic Energy Sciences (May 2021)
- Awarded American Vacuum Society 66 Dorothy M And Earl S Hoffman Travel Grant (Sep 2019)
- Won Best Poster at Nanoscale and Quantum Phenomena Institute poster session, Ohio University (Nov 2018)
- Awarded Ohio University Nanoscale and Quantum Phenomena Institute travel award (Oct 2018)
Timeline
Student Research Associate
Argonne National Laboratory
06.2021 - Current
Master of Science - Physics
Ohio University
08.2017 - 08.2018
Graduate Student Researcher
Ohio University
05.2017 - Current
Doctor of Philosophy - Physics
Ohio University
08.2016 - Current
Undergraduate Student Researcher
University Of Colombo, Sri Lanka
01.2014 - 02.2015
Bachelor of Science (Honors) - Physics
University of Colombo
08.2010 - 01.2015
Selected Publications
- T. Ajayi , V. Singh , K. Z. Latt , S. Sarkar , X. Cheng , S. Premarathna , N. Dandu , S. Wang , F. Movahedifar , S. Wieghold , N. Shirato , V. Rose , L. Curtiss , A. Ngo , E. Masson , S. W. Hla. Atomically precise control of rotational dynamics in charged rare-earth complexes on a metal surface. Nature Communications 13, 6305 (2022).
- T. Ajayi , N. Shirato , T. Rojas , S. Wieghold , X. Cheng , K. Z. Latt , D. Trainer , N. Dandu , Y. Li , S. Premarathna , S. Sarkar , D. Rosenmann , Y. Liu , N. Kyritsakas , S. Wang , Eric Masson , V. Rose , X. Li , A. Ngo, S. W. Hla. Elemental and Chemical Characterizations of Just One Atom using Synchrotron X-rays (In review at Nature, 2022)
- S. Premarathna , K. A. I. L. W. Gamalath, "Simulation of Isotropic Acoustic Metamaterials", International Letters of Chemistry, Physics and Astronomy, Vol. 65, pp. 43-52, (2016)
- S. Premarathna , K. A. I. L. W. Gamalath, "Acoustic cylindrical cloak",World Scientific News, Vol. 47, pp. 76-88, (2016)
Selected Presentations
Oral Presentations
•"Chiral Rare-Earth Molecular Clusters." American Physical Society March meetings (2022).
•"Scanning Tunneling Microscopy Investigations of Molecules Adsorbed on Semiconducting Graphene Nanoribbons." American Vacuum Society Fall meetings (2019)
Poster Presentations
•"Electronic and Vibronic Properties of Single Molecules in Molecule/Graphene Nanoribbon/Au(111) Heterostructures ." American Physical Society March meetings (2022).