Professor Cather Simpson

Biography

Cather Simpson joined the University of Auckland in 2007, with a joint appointment in Physics and the Chemical Sciences. She received her Ph.D. in the USA in Medical Sciences with a focus on the ultrafast vibrational dynamics of heme proteins. After a Department of Energy Distinguished Postdoctoral Fellowship, she joined the Chemistry Department at Case Western Reserve University as an Assistant Professor to pursue research in ultrafast energy conversion in molecules. After earning tenure and promotion at CWRU, she moved to the University of Auckland, where her research now spans fundamental spectroscopy to applied device development.

Research | Current

Ultrafast Spectroscopy and Quantum Chemistry. The ability of molecules to convert light into more useful forms of energy motivates our fundamental chemical physics research. How molecules direct the energy acquired in light absorption, and “choose” among potential paths (electron transfer, mechanical motion, bond breaking and forming, fluorescence, vibrational energy dissipation, etc.) is the focus of our studies on the dynamics of hemes, diphosphenes, red-lake art chromophores, porphyrin-fullerene complexes, and others. We use pump-probe spectroscopy (transient absorption, Raman) on the femtosecond to microsecond timescales to probe these molecular dynamics, and quantum chemical calculations (CASSCF, CASPT2, DFT, TDDFT) to understand them. Ultimately, we seek knowledge of how the structure and environment influence molecular “decisions” so that we can both predict and tailor photochemical and photophysical behaviour.

Pulsed Laser Micromachining and Microfabrication.  Our interest in laser-matter interactions has led to major targeted research projects to exploit ultrashort laser pulses for machining. Femtosecond pulse durations lead to multiphoton excitations and temporal uncoupling of electron and phonon degrees of freedom, and offer smaller features, minimal heat affected zones, and breadth in materials suitable for processing. Unfortunately, femtosecond laser machining is still too slow to be of widespread industry use. I lead a multi-institutional team to overcome this challenge through tailored laser-matter interactions, materials synthesis, and laser development. Our lab focuses on the first of these, with temporal and spatial shaping, multi-pulsing, frequency sweeping, and other approaches. Our studies on metals, dielectrics, biomaterials and polymers, seek to illuminate and better exploit the mechanistic details of laser ablation. NZ and US commercial partners help target our research to meet commercially valuable challenges, so that we advance high-tech manufacturing by mobilizing new knowledge.

Sperm Sorting by Sex for Agriculture. Engender Technologies, Ltd., a spin-off company funded by venture capital and Auckland UniServices, commercializes our ideas for using microfluidic and photonic technology to improve sorting of sperm by sex for the dairy industry. I am the founding scientist and chief science officer. Our new technology (PCT published Jan 2014) will improve both efficiency of sorting and performance of sex-sorted sperm by avoiding electric fields and reducing shear stress on the sperm membrane during processing. All components have been proven in the lab, and the project is now in the last laboratory demonstration stage before commercialization. Engender recently signed a deal with one of the world’s largest AI companies. The deal provides Engender with crucial expertise in sperm morphology, viability and handling and in vitro validation and fertilisation testing of sperm sorted by Engender’s technology.

Teaching | Current

My teaching philosophy is simple: my job as a university academic is to help students learn what they need in order to succeed in their own lives. Achieving this goal is my primary reason for building a career academia. Whether I am lecturing on chemistry or physics to a class of 500+ engineers or pre-medical students, on advanced quantum mechanics to 15 Ph.D. students, or on science and metaphor to arts and humanities students, this core value spurs me to always look for ways to help students perform to the best of their abilities. I strive for continued improvement in my courses with innovations based on sound pedagogical research, and have achieved success with collaborative learning, clear expectations, a focus on concepts rather than memorization, and by listening to the formative and summative feedback from students and colleagues. This philosophy extends to one-on-one research supervision, to curricular development, and to outreach to schools and the community. I am particularly keen to improve engagement with and outcomes for women and other underrepresented groups.

Currently, I lead an educational research project that examines student motivations, strategies for learning and study habits in large lecture “science major” and “service” classes that is directed at understanding how to better understand and foster success for both cohorts. I also chair a team of academic and professional staff who are implementing the new “Science Scholars Programme” in the Faculty of Science at the University of Auckland. Guided by international “best practice” in honours programs, we are designing an enriched science curriculum for NZ’s best science students, with diversity a key target at the outset. Our goal is to develop a community of scholars that fosters creativity, innovation, and achievement. The first Science Scholars will begin study in 2015.

Postgraduate supervision

CURRENT OPENING:   Photophysics of Molecular Dragons

Molecules that can control the flow of excess vibrational energy after photoexcitation can be turned into molecular dragons: focusing their non-Boltzman relaxation energy towards therapeutic targets . Phthalocyanines and porphyrins are good candidates for molecular dragons because they have a large number of substitution sites that allows them to be tailored for these applications. The designs of these systems relies on a thorough understanding of the dynamics in the photoexcited state of the molecule, which can be studied using femtosecond time-resolved spectroscopy such as femtosecond transient absorption, time-resolved Raman and time-resolved fluorescence spectroscopy. The successful candidate will have a strong interest in photophysics, photochemistry, and free-space laser spectroscopy setups. The project will use all three of these methods to evaluate dragon-like behaviour in molecules synthesised by collaborators.

Current PhD Students:

•  Sarah Thompson (Chemistry)
•  Julie Kho (Chemistry)
•  Andy Wang (Chemistry)
•  Nina Novikova (Chemistry; co-supervised with Prof. Penny Brothers)
•  Simon Ashforth (Physics)
•  Dijana Bogunovic (Physics)
•  Matheus Vargas (Chemistry)

Current MSc Students:

•  Jake Martin (Chemistry)

Distinctions/Honours

• 2013               National Tertiary Teaching Excellence Award, Ako Aotearoa National Centre for Tertiary Teaching Excellence (NZ).
• 2013               Callaghan Commercialisation Fellowship, MacDiarmid Institute for Advanced Materials and Nanotechnology (NZ).
• 2012               The University of Auckland Sustained Excellence in Teaching Award (NZ).
• 2012               Dean's Award for Teaching Excellence, University of Auckland (NZ).
• 1998 – 2004    F.I.R.S.T Award (R29), National Institutes of Health (USA)
• 1999 – 2000    Glennan Fellow Award for Young Teacher Scholars, Case Western Reserve University (USA).
• 1998               “Top Prof” Award, CWRU Mortar Board Society, Case Western Reserve University (USA)
• 1994 – 1996    Department of Energy Distinguished Postdoctoral Research Fellow (USA).
• 1989 – 1994    Howard Hughes Predoctoral Fellow (USA).
• 1983 – 1986    Echols Scholar at the University of Virginia (USA).

Responsibilities

Director, The Photon Factory.  The Photon Factory is a state-of-the-art pulsed laser research facility in the Faculty of Science at the University of Auckland. The Photon Factory’s core mission is to enable the research of all New Zealand scientists – academic, industrial, and national research lab-based – through the advanced use of laser pulses to interrogate light-matter interactions and to manipulate and machine materials. Opened in 2010, we have grown rapidly to a now vibrant group of about 25 researchers that includes physics, chemistry and engineering students and staff working together to perform research of our own, and to undertake research for industry and collaborators. Since 2010, we have generated nearly $1.6M (NZD) in commercial contracts, completed or ongoing. Our external grant revenues are strong as well, with over $9M (NZD) in funding, most as principal investigators. Finally, we also actively reach out to schools with science projects with school students, school visits and tours, and with teachers through professional teaching societies and the Royal Society of New Zealand.

Centres of Research Excellence.  Dr. Simpson is a Principal Investigator in the MacDiarmid Institute for Advanced Materials and Nanotechnology and in the new Dodd-Walls Centre for Photonic and Quantum Technologies, where she also sits on the Executive Committee.  She is also an Associate Investigator in the Medical Devices CoRE.