Koh Enshan Dax

Biography

Dr Koh Enshan Dax is an Adjunct Assistant Professor at SUTD and a Senior Scientist at the Institute of High Performance Computing (IHPC) under the Agency for Science, Technology and Research (A*STAR), Singapore. He is also an Investigator at the A*STAR Quantum Innovation Centre (Q.Inc) and an Editor at the journal Quantum.

Previously, Dr Koh was a Z-Fellowship Postdoctoral Researcher at Zapata Computing (now Zapata AI) in Boston, MA, USA. Dr Koh was a recipient of A*STAR’s National Science Scholarship (NSS BS-PhD) and the A*STAR Science and Engineering Research Council (SERC) Central Research Fund (CRF) Award for Use-Inspired Basic Research.

Dr Koh received the B.S. degree in Mathematics and Physics from Stanford University (Stanford, CA, USA); the M.Sc. degree in Physics from the University of Waterloo (Waterloo, ON, Canada) in conjunction with the Perimeter Scholars International certificate from the Perimeter Institute for Theoretical Physics (Waterloo, ON, Canada); and the Ph.D. degree in Mathematics from the Massachusetts Institute of Technology (Cambridge, MA, USA).

Education

• Ph.D., Mathematics, Massachusetts Institute of Technology, USA (2019)
• M.Sc., Physics, Perimeter Scholars International, Perimeter Institute for Theoretical Physics and University of Waterloo, Canada (2013)
• B.S., Mathematics and Physics – double major, Stanford University, USA (2011)

Awards

• Awarded IOP Trusted Reviewer Status, IOP Publishing (2023).
• Central Research Fund Award, A*STAR Science and Engineering Research Council (2022).
• National Science Scholarship (PhD), A*STAR (2013).
• Chairman’s Honours List, A*STAR (2011).
• National Science Scholarship (BS), A*STAR (2006).

Research Interests

Quantum computation, quantum algorithms, quantum complexity theory, classical simulation of quantum computation, and quantum foundations

Selected Publications

• Fong Yew Leong, Dax Enshan Koh, Jian Feng Kong, Siong Thye Goh, Jun Yong Khoo, Wei-Bin Ewe, Hongying Li, Jayne Thompson, and Dario Poletti, “Solving fractional differential equations on a quantum computer: A variational approach.” AVS Quantum Science 6, 033802 (2024).
• Kaifeng Bu, Roy J. Garcia, Arthur Jaffe, Dax Enshan Koh, and Lu Li, “Complexity of Quantum Circuits via Sensitivity, Magic, and Coherence.” Communications in Mathematical Physics 405, 161 (2024).
• Bujiao Wu and Dax Enshan Koh, “Error-mitigated fermionic classical shadows on noisy quantum devices.” npj Quantum Information 10, 39 (2024).
• V. Vijendran, Aritra Das, Dax Enshan Koh, Syed M. Assad, and Ping Koy Lam, “An expressive ansatz for low-depth quantum approximate optimisation.” Quantum Science and Technology 9, 025010 (2024).
• Kaifeng Bu, Dax Enshan Koh, Roy J. Garcia, and Arthur Jaffe, “Classical shadows with Pauli-invariant unitary ensembles.” npj Quantum Information 10, 6 (2024).
• Fong Yew Leong, Dax Enshan Koh, Wei-Bin Ewe, and Jian Feng Kong, “Variational quantum simulation of partial differential equations: applications in colloidal transport.” International Journal of Numerical Methods for Heat & Fluid Flow 33, 3669 (2023).
• Kaifeng Bu, Dax Enshan Koh, Lu Li, Qingxian Luo, and Yaobo Zhang, “Effects of quantum resources and noise on the statistical complexity of quantum circuits.” Quantum Science and Technology 8, 025013 (2023).
• Amara Katabarwa, Sukin Sim, Dax Enshan Koh, and Pierre-Luc Dallaire-Demers, “Connecting geometry and performance of two-qubit parameterized quantum circuits.” Quantum 6, 782 (2022).
• Dax Enshan Koh and Sabee Grewal, “Classical Shadows with Noise.” Quantum 6, 776 (2022).
• Fong Yew Leong, Wei-Bin Ewe, and Dax Enshan Koh, “Variational quantum evolution equation solver.” Scientific Reports 12, 10817 (2022).
• Kaifeng Bu, Dax Enshan Koh, Lu Li, Qingxian Luo, and Yaobo Zhang, “Statistical complexity of quantum circuits.” Physical Review A 105, 062431 (2022).
• Dax Enshan Koh, Guoming Wang, Peter D. Johnson, and Yudong Cao, “Foundations for Bayesian inference with engineered likelihood functions for robust amplitude estimation.” Journal of Mathematical Physics 63, 052202 (2022).
• Wei-Bin Ewe, Dax Enshan Koh, Siong Thye Goh, Hong-Son Chu, and Ching Eng Png, “Variational Quantum-Based Simulation of Waveguide Modes.” IEEE Transactions on Microwave Theory and Techniques 70 (5), 2517–2525 (2022).
• Kaifeng Bu and Dax Enshan Koh, “Classical Simulation of Quantum Circuits by Half Gauss Sums.” Communications in Mathematical Physics 390, 471–500 (2022).
• Guoming Wang, Dax Enshan Koh, Peter D. Johnson, and Yudong Cao, “Minimizing Estimation Runtime on Noisy Quantum Computers.” PRX Quantum 2, 010346 (2021).
• Alexander M. Dalzell, Aram W. Harrow, Dax Enshan Koh, and Rolando L. La Placa, “How many qubits are needed for quantum computational supremacy?” Quantum 4, 264 (2020).
• Jacob D. Biamonte, Mauro E. S. Morales, and Dax Enshan Koh, “Entanglement scaling in quantum advantage benchmarks.” Physical Review A 101, 012349 (2020).
• Kaifeng Bu and Dax Enshan Koh, “Efficient Classical Simulation of Clifford Circuits with Nonstabilizer Input States.” Physical Review Letters 123, 170502 (2019).
• Adam Bouland, Joseph F. Fitzsimons, and Dax Enshan Koh, “Complexity Classification of Conjugated Clifford Circuits.” In 33rd Computational Complexity Conference (CCC 2018). Leibniz International Proceedings in Informatics (LIPIcs), Volume 102, pp. 21:1-21:25, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2018).
• Dax Enshan Koh, Murphy Yuezhen Niu, and Theodore J. Yoder, “Quantum simulation from the bottom up: the case of rebits.” Journal of Physics A: Mathematical and Theoretical 51, 195302 (2018).
• Dax Enshan Koh, Mark D. Penney, and Robert W. Spekkens, “Computing quopit Clifford circuit amplitudes by the sum-over-paths technique.” Quantum Information & Computation 17 (13&14), 1081–1095 (2017).
• Mark D. Penney, Dax Enshan Koh, and Robert W. Spekkens, “Quantum circuit dynamics via path integrals: Is there a classical action for discrete-time paths?” New Journal of Physics 19, 073006 (2017).
• Dax Enshan Koh, “Further extensions of Clifford circuits and their classical simulation complexities.” Quantum Information & Computation 17 (3&4), 0262–0282 (2017).
• Zi-Wen Liu, Christopher Perry, Yechao Zhu, Dax Enshan Koh, and Scott Aaronson, “Doubly infinite separation of quantum information and communication.” Physical Review A 93, 012347 (2016).
• Dax Enshan Koh, Michael J. W. Hall, Setiawan, James E. Pope, Chiara Marletto, Alastair Kay, Valerio Scarani, and Artur Ekert, “Effects of Reduced Measurement Independence on Bell-Based Randomness Expansion.” Physical Review Letters 109, 160404 (2012).
• M. J. Ma, M. B. A. Jalil, S. G. Tan, and D. E. Koh, “Spin-flip assisted tunneling through quantum dot based magnetic tunnel junctions.” The European Physical Journal B 82, 37–46 (2011).
• Jie Guo, Seng Ghee Tan, Mansoor Bin Abdul Jalil, Dax Enshan Koh, Guchang Han, and Hao Meng, “Self-consistent treatment of spin and magnetization dynamic effect in spin transfer switching.” Journal of Magnetism and Magnetic Materials 323, 83–87 (2011).
• Seng Ghee Tan, Mansoor Bin Abdul Jalil, Dax Enshan Koh, and Hwee Kuan Lee, “Pseudospin-orbital coupling for pseudospintronic device in graphene.” Journal of Magnetism and Magnetic Materials 322, 2390–2394 (2010).