Valerian H. Hall-Chen
University of Oxford (2016 – present)
DPhil in Theoretical Physics
I am working towards a DPhil (PhD) under the supervision of Felix Parra (University of Oxford) and Jon Hillesheim (Culham Centre for Fusion Energy). My work is focused on measuring and understanding turbulence in fusion plasmas. I am developing a model for the interaction between microwaves and turbulent density fluctuations to analyse and interpret data from the Doppler Backscattering (DBS) diagnostic. DBS is especially important for future tokamaks as it is one of the few available diagnostics which are robust enough to withstand high neutron fluxes. For a layman-friendly introduction to nuclear fusion, consider listening to our Oxford podcast.
University of Cambridge (2012 – 2015)
B.A. (Hons) in Natural Sciences, Double First Class Honours
- Part IA: Physics, Materials Science, Computer Science, Mathematics.
- Part IB: Physics A, Physics B, Mathematics.
- Part II: Experimental and Theoretical Physics.
National Junior College (2008 – 2009)
Singapore-Cambridge GCE Advanced Level
- H2: Physics (A), Chemistry (A), Mathematics (A), Knowledge & Inquiry (A)
- H3: Essentials of Modern Physics (Dist), Science Research (Dist)
Institute of Materials Research and Engineering, A*STAR (2016 – 2016)
Specialist I (with Joel Yang)
I worked on novel structures for 2D and 3D colour printing near and at the diffraction limit.
Institute of High Performance Computing, A*STAR (2015 – 2016)
Research Engineer (with Jason Png)
I worked in the plasmonics and photonics group, supervised by Jason Png. My work fell into two broad categories. The first focused on understanding and designing metasurfaces using FDTD simulations. The second involved studying the properties, such as losses and birefringence, of nonlinear photonic waveguides of various geometries. I also co-supervised three high school student interns.
Republic of Singapore Air Force (2010-2012)
I was drafted into the military for two years. For the most part, I served in ground logistics at the Peace Prairie Detachment in Texas, a joint chinook detachment between the Republic of Singapore Air Force (RSAF) and the Texas Army National Guard.
 Y Liu, H Wang, J Ho, RC Ng, RJ Ng, VH Hall-Chen, EH Koay, Z Dong, H Liu, CW Qiu, JR Greer, JKW Yang, Structural color three-dimensional printing by shrinking photonic crystals, Nature Communications 10, 4340 (2019).
 JR Ong, HS Chu, VH Chen, AY Zhu, P Genevet, Freestanding dielectric nanohole array metasurface for mid-infrared wavelength applications, Optics Letters 42 (13), 2639-2642 (2017).
 VH Chen, JR Ong, CE Png, Polarisation independent silicon-on-insulator slot waveguides, Scientific Reports 6, 37760 (2016).
 S Peng, R Zhang, VH Chen, ET Khabiboulline, P Braun, HA Atwater, Three-dimensional single gyroid photonic crystals with a mid-infrared bandgap, ACS Photonics 3 (6), 1131–1137 (2016).
 JR Ong and VH Chen, Optimal geometry of nonlinear silicon slot waveguides accounting for the effect of waveguide losses, Optics Express 23, 33622-33633 (2015).
 NL Yakovlev, YY Tay, ZJ Tay, HV Chen, Distribution of switching fields in thin films with uni-axial magnetic anisotropy, Journal of Magnetism and Magnetic Materials 329, 170-177 (2013).
 NL Yakovlev, H Chen, K Zhang, Two-axis magnetisation analysis of epitaxial cobalt films, Journal of Nanoscience and Nanotechnology 11, 2575-2578 (2011).
L Wu, VH Chen, P Bai, S Sun. Localized polaritons of multi-particle systems. In Nanophotonics and Plasmonics: An Integrated View, Eds. YA Akimov and CE Png, CRC Press (2017).
Conferences and Seminars
VH Hall-Chen, FI Parra, JC Hillesheim, Modelling the effects of misaligning the probe beam and magnetic field in Doppler backscattering measurements, oral presentation, 14th International Reflectometry Workshop (2019).
VH Chen, FI Parra, JC Hillesheim, Effects of misaligning the probe beam and magnetic field in Doppler backscattering measurements, poster presentation, 45th European Physical Society Conference on Plasma Physics (2018).
VH Chen, FI Parra, JC Hillesheim, Doppler backscattering measurements of fusion plasmas, technical seminar, IEEE NPSS (Singapore Chapter) (2017).
H Chen, YY Tay, ZJ Tay, YJ Nguoi, NL Yakovlev, Magnetic and optical properties of cobalt thin films with uniaxial anisotropy, poster presentation, International Conference for Young Researchers on Advanced Materials (2012)
Honours, Awards, and Fellowships
Carter Prize (2015) – For outstanding results in the Tripos examinations.
Caltech Summer Undergraduate Research Fellowship (2014)
Caldwell Scholarship (2013) – For outstanding results in the Tripos examinations.
A*STAR National Science Scholarship (2010) – Provides full funding for undergraduate and postgraduate studies.
Lee Kuan Yew Award for Mathematics and Science (2010)
Singapore Science and Engineering Fair, Gold Award (2009)
A*STAR Talent Search, Commendation (2009)
A*STAR Scholars’ Network (2015-2016)
We organise seminars and social events to increase cohesiveness within the scholar community as well as to link our members with prominent figures in academia, the industry, and the public sector. In addition, I am heavily involved in outreach efforts, promoting science and the various A*STAR scholarships to junior college and secondary school students who might otherwise not have developed an interest in them.
Cambridge University Physics Society (2014-2015)
As one of two co-chairs, I was joint leader of the several-hundred members strong CU Physics Society. We invited physicists from a wide variety of fields to give talks about their research. Over the course of the academic year, we held 17 talks, which was more than in any previous year. Some of these talks are available on our YouTube Channel. Among our speakers, we welcomed both Nobel and Ig-Nobel prize winners, on top of an already very distinguished guest list. We were told that various members of the Cavendish made use of the opportunity of our speakers being in Cambridge to meet up for discussion and collaboration. My committee’s impact stretched far beyond the undergraduate community, and I am proud of that.
California Institute of Technology (Summer 2014)
Summer Undergraduate Research Fellow (supervised by Harry Atwater)
I fabricated photonic gyroid crystals using 3D two-photon lithography. The aim was to make structures with Weyl points. I characterised the samples with Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy, to check how well the samples were grown and whether their properties agreed with those I predicted by performing FDTD simulations.
Data Storage Institute (Summer 2013)
Research Intern (supervised by Kwaku Eason)
We simulated the behaviour of macrospins coupled to the bath, the understanding of which is important for heat assisted magnetic recording. Using an in-house Fortran program to solve the stochastic Landau-Lifshitz-Bloch equation numerically, I shed light on the stability and reversal of macrospins under different conditions.
Institute of Materials Research and Engineering (Summer 2008-2010 and 2012, Winter 2008)
Research Intern (supervised by Nikolai Yakovlev)
I contributed to the development of in-house characterisation equipment, including the only two-axis vibrating sample magnetometer in Singapore. We characterised various magnetic thin films. One of the properties we studied was the switching field distribution (SFD) of such thin films. I helped to develop a new method of determining the intrinsic SFD from the extrnsic SFD. We also modelled magnetisation reversal and hysteresis loops.