The Rosenthal Group

(Left to right): Sandy, Toshia, Scott, Xochitl, Noah, James, Talitha, and Joe.

Research Assistant Professors

Ian Tomlinson

Ian obtained his B.Sc. in 1985 from Essex University and his Ph.D. in Biological Chemistry in 1989 from Essex University in the UK. After many years in industry at ASTRA (London and Sweden) and at Key Organics he took a sabbatical and received an M.Sc. from Cranfield University in Environmental Diagnostics in 2000. After which came to the States to work in our group on the nano-neuro project. His principle role is to design and synthesize novel biologically active ligands that can be attached to nanocrystals and used as biological fluorescent probes in neurology.

James McBride

James received his B.S. from Florida Southern College in 1999 and his Ph.D. from Vanderbilt in 2004. James' interests lay in using Z-Contrast Scanning Transmission Microscopy (Z-STEM) and Electron Energy-Loss Spectroscopy (EELS) to elucidate the atomic structure and composition of CdSe nanocrystals and CdSe/ZnS core/shells and their surfaces. This work is in collaboration with Stephen Pennycook at Oak Ridge National Laboratory. Rutherford Back-Scattering has also been used to analyze the bulk composition of the core/shell samples and to identify impurities found in the semi-conducting polymer used in our photovoltaic devices.

Visit James' researcher ID.

Current Members

Amy Ng

Amy graduated from Suffolk University in Boston, MA with a B.S. in chemistry (2009). Her research pertains to hybrid nanocrystal/polymer photovolatics, electron microscopy (SEM, dual-beam FIB SEM, TEM, STEM), and electron beam-induced current (EBIC). Utilizing both EM and EBIC, electronic activity mapping correlation with physical sample characteristics via EM is the core component of her project. This work is in collaboration with MTSU (FIB SEM) and Oak Ridge National Laboratory (STEM, EBIC) under Stephen J. Pennycook and Donovan N. Leonard. She is currently a visiting research assistant at ORNL.
Amy also enjoys outreach activities promoting science and nanotechnology.

Joe Keene

Joe received his B.S. in Chemistry from Wake Forest University in 2009. His current research utilizes Ultrafast Fluorescence Upconversion Spectroscopy to study the charge carrier dynamics of semiconductor quantum dots. He is interested in manipulating nanocrystal surface and chemical composition to exhibit control over charge carrier behavior. Joe spends his days in the laser lab learning the various personalities of our ultrafast laser system

Scott Niezgoda

Scott received his B.S. from Saint Joseph's University in Philadelphia in 2010, and joined the lab in July of the same year. When he's not brewing beer, camping, or playing guitar, Scott's interests lie in the implementation of non-toxic quantum dots into solid-state solar cells. His current research involves localized surface plasmon resonance modes in quantum dots, and their implementation into low-defect thin films for eventual application to photovoltaics.

Toshia Wrenn

Toshia earned her ACS-certified BS in Chemistry from Austin Peay State University in 2010. Her undergraduate research delved into nanosilver preparation and characterization.
She joined the Rosenthal group in January 2011 and is currently researching third generation solar cells; particularly nanostructured, solid-state designs.

Noah Orfield

Noah received his B.S. in Chemistry from the University of Colorado at Colorado Springs in 2010. He joined the Rosenthal lab in January of 2011.

Noah is currently working on an instrument to allow for imaging and analysis of single ultrasmall white light emitting CdSe nanocrystal fluorescence, with special emphasis on the fluorescence intermittency of these nanocrystals. He is also interested in the effects of shell size and organic ligand identity on the photophysics of single core/shell inorganic nanocrystals, and time-resolved three dimensional tracking of individual quantum dots in solution.

Xochitl Arzeta-Ferrer

Xochitl joined the Rosenthal group in early 2013 where her interests lie in the biological research aspects of the group.

Talitha Frecker

Talitha joined the lab in early 2014 - she is working on the white light nanocrystal part of the group.


Past Members: PhDs | Masters | Interns


Michael Bowers

Mike received a Ph.D. from the group in 2007. He is currently at BAE Systems.

Jerry Chang

Jerry received his B.S. from National Taiwan University in Taiwan. He joined the group in the summer of 2006. Jerry is particularly interested in biomedical applications of Quantum Dots in vitro and in vivo. His current research work involves the development of QD-based probes for fluorescent imaging.

Jerry is currently at Rockefeller University working under Nobel laureate Paul Greengard.

NB: Jerry is also the group's resident photographer -- the majority of the pictures on this website were taken by Jerry!

Albert Dukes III

Albert graduated from Clemson University with a B.S. in Chemistry in 2005. His current work involves detailed spectroscopic characterization of white-light CdSe nanocrystals. In his spare time Albert enjoys watching sports playing with his pet cockatoo, Kiko.

Albert graduated with a Ph.D. from the group in May of 2011. He is currently an assistant professor at Lander University. Please visit his Lander webpage.

Margaret Erwin

Meg currently holds the position of content development leader at McGraw-Hill.

Danielle Garrett

Danielle received her B.S with a major in Chemistry and a minor in English from the University of Tennessee at Knoxville in 2004. For the past three years, her research has focused on the use of ultrafast fluorescence upconversion to explore the carrier dynamics of cadmium chalcogenide nanocrystals. Recently, this spectroscopic technique has been used to study the dynamics of ultra-small CdSe nanocrystals that emit broad spectrum white light. Additionally, her research has focused on the change in carrier dynamics associated with changes in synthetic methods. Specifically, she has looked at the change in dynamics of cadmium chalcogenide nanocrystals associated with varying ligands and composition. Using CdO as a synthetic precursor, she has synthesized CdSe nanocrystals with various surface ligands (tri-n-octylphosphine oxide/hexadecylamine (TOPO/HDA) and oleic acid (OA)). Most recently, she has been examining the relaxation dynamics of CdSxSex-1 alloy nanocrystals. Alloy nanocrystals offer the added advantage of composition-dependent tunability. While ultrafast studies have been conducted on bulk CdSxSex-1 alloys, there has been no focus on their nanocrystal counterpart. Looking forward, a more intimate understanding of the dynamics of the nanocrystals will allow the parameters of these materials to be tailored for applications such as solid-state lighting (white light CdSe) and potential biological imaging agents (CdSxSex-1).

Danielle graduated from the group with a Ph.D. in 2008. She is currently teaching at Belmont University.

Melissa Harrison

Melissa defended her dissertation on September 17th, 2012. She is currently at Intel in Phoenix, AZ.

Tadd Kippeny

Tadd received a Ph.D. from the group in 2005. He is currently a principle engineer at BAE Systems.

Oleg Kovtun

Oleg received his A.S. in chemistry from Madisonville Community College in 2005 and B.S. in chemistry from Murray State University in 2007. Oleg joined the group following summer rotation in 2008. His research focused on the development of drug-conjugated quantum dots for specific labeling of the Dopamine Transporter (DAT) protein and the use of fluorescence microscopy techniques for single-quantum dot tracking of the membrane dynamics of DAT molecules under various stimuli. Oleg defended his dissertation on November 15th, 2013 and will be joining McCoy & McCoy Laboratories in January, 2014.

LinkedIn Profile

Rebecca Orndorff

Michael Schreuder

Michael Schreuder was born in San Cristobal, Chiapas, Mexico in 1983. He attended Pella High School in Iowa, before going to Northwestern College. He received a BA in Chemistry, as well as played soccer and lacrosse. Michael was married in December of 2004 to Mary-Celeste; they currently have a dog named Amelie. Michael came to Vanderbilt University in the summer of 2005 and worked on incorporating nanocrystals into devices.

Michael graduated in 2010 with a Ph.D. He is currently in England working for Sharp Electronics.

Nathanael Smith (former research associate)

Nat did his undergraduate and graduate studies at the Australian National University in Canberra, Australia. For his PhD, he studied the optical properties of silicon nanocrystals embedded in a silicon dioxide waveguide. In particular, he was interested in exploring whether silicon nanocrystals could exhibit optical gain and thus serve as the gain medium in a silicon based laser. He joined the Rosenthal group in March, 2006, where he has been involved in research into white light CdSe nancocrystals and nanocrystals sensitized solar cells.

Nat is currently an assistant professor of physics and astronomy at Middle Tennessee State University, where he is continuing to research nanocrystals and their application to photovoltaics. Please visit his MTSU webpage for his current courses.

Laura Swafford

Laura graduated from Vanderbilt with a Ph.D. in 2006.

David Underwood

Dave (Ph.D., 2000) has established himself in scientific patents in Minnesota with his company Underwood and Associates, LLC where he serves as the president.

Michael Warnement

Mike received his B.S. in Chemistry from the University of Dayton in 2001. Following a brief one-and-half year stint in the real world he decided it was best to give up and become a student once more. This time, he figured the best case scenario would be to commit at least 4-5 years of his already aging existence to the pursuit of knowledge (i.e. putting off finding a job). Mike's research is focused towards the development of quantum dot conjugates for biological imaging applications. Recent advances utilizing antibody-conjugated QD probes will ultimately allow investigations into the trafficking and localization of membrane bound receptors in response to applied stimuli.

Mike obtained a Ph.D. from Vanderbilt in 2009. He is currently working at STEMCELL Technologies.

Masters (2009 - present)

Sarah Harrell

Sarah received a B.S. in Chemistry and a BS in Physics from Belmont University in 2010. She joined the group in the winter of 2011. Sarah is interested in ultrsmall nanocrystals and incorporating these nanocrystals into devices for the purpose of making white LEDs.

Emma Hughes

Emily Ross

Emily received her B.S. in Chemistry and Biology from the University of Alabama in Huntsville. After spending a few years working for Thermo Scientific, she joined the Rosenthal lab's "bioside" in 2010. Her projects focused on strategies toward the development of quantum dot-based live-cell pharmacological assays aimed at membrane transporters and receptors probe design. Graduating in May 2013 with her masters in Chemistry, Emily is continuing her Ph.D. work in the Vanderbilt Chemical and Physical Biology Graduate Program in the lab of Dr. Gregg Stanwood.

Shawn Rosson

Teresa Rosson

Jessica Sammons

Jessica received her Masters in Chemistry from Vanderbilt and is currently pursuing her PhD at the University of Pittsburg.


Charlotte Dossin

Charlotte worked with Noah in the white light part of the group.

Elly Earlywine (former REU - Summer 2011)

Elly recently graduated from Hope College with a bachelor's in chemistry. Emily was Elly's mentor.

Ashley Lanquist (shadowing high school student)

Ashley, from Harpeth Hall, visited the group during her Winterim in January of 2013. She shadowed both Joe and Noah to learn about scientific research. Her blog about her experience can be found here.

Rory Locke (former undergrad, TN-SCORE REU - Summer 2011 to Spring 2012)

Rory is completing his last year at MTSU in physics. His work in the group pertained to synthesis of hybrid nano-architectures in the realm of solar applications. Amy was Rory's mentor.

Barclay Randall (former TN-SCORE REU - Summer 2012)

Clay is currently at MTSU. He worked under Toshia during his REU. His internship was preceded by a lab visit after his graduation from Hume Fogg High School - the group recruited him for the internship.

Scott Surles (former TN-SCORE REU - Summer 2011)

Scott is currently at MTSU pursuing studies in physics. Scott was his mentor during his REU.

Eugene Yap

Scott was Eugene's mentor in the solar side of the group.