Ho Shen Yong
Senior Lecturer
(65) 6592 7816

BSc (Hons), Imperial College; PGDE (Distinction), NTU-NIE;
MSc & PhD, University of Toronto

Research Area: Theory and Computation
Research Interests
Techniques for solving quantum many-body problems

The traditional method of finding eigenvalues of a Hamiltonian is by
diagonalization. However, in realistic quantum many-body systems the Hamiltonian matrices can often be huge and computationally intractable. The problem is then to find approximation schemes such that the salient features of the Hamiltonian are retained. My research involves developing techniques that will yield accurate approximations of the eigenstates of quantum many body models and from there derive the dynamics of the system. For example, using a Shifted Harmonic Approximation, I have successfully derived the BCS gap equations for a finite multi-level system without using the BCS ansatz.
At present, I am exploring possibilities of constructing simple solvable models involving qubit systems interacting non-linearly with an anharmonic environment. It is hoped that such models will enable us to better understand quantum decoherence.

Foundational issues in Quantum Mechanics

I am also interested in acquiring a deeper under-standing of counter-intuitive phenomena that gave quantum mechanics its weirdness. Some of these include single particle interference, correlations of entangled pairs in the context of EPR-Bell type experiments and the Aharonov-Bohm effect. It is hoped that new insights can be acquired and that they will allow us to better understand the enigmatic quantum mechanics.

An area of practical interest related to the studying of decoherence is that if the environment interacting with a quantum system could possibly enhance quantum coherence instead of destroying it. This is of particular importance in complex systems – for example, do certain biological processes in nature already inherently exploit and preserve quantum coherence? If so, can we learn from nature and mimic this aspect for our applications.

Physics Education Research
For Physics, the variety of approaches adopted by the beginner to learn the subject is probably more diverse than other science disciplines. I am exploring if there are systematic ways of classifying the various styles of learning foundational Physics and henceforth develop the most effective way to teach the subject to a large class of students with diverse backgrounds. In due time, I hope to extend the similar analysis to core Physics courses such as mechanics, electrodynamics, quantum mechanics and relativity (both special and general).
Selected Publications
Ho, S. Y.; Rosensteel, G.; Rowe, D. J. Equations-of-Motion Approach to Quantum Mechanics: Application to a Model Phase Transition. Phys. Rev. Lett. 98, 080401 (2007).
Rosensteel, G.; Rowe, D. J.; Ho, S. Y. Equations of motion for a spectrum-generating algebra: Lipkin-Meshkov-Glick model. J. of Phys. A: Math. 41, 025208 (2008).
Ho, S. Y.; Rowe, D. J.; S. De Baerdemacker Eigenstates Estimation of the Bardeen-Cooper-Schriefer (BCS) Hamiltonian for large finite systems. (arXiv:1011.4304v1 [quant-ph]) (2010).
Foong, S. K.; Lim, C. H.; Ho, S. Y.; Wong, D.; Kuppan, L. Experiments for Challenging Topics in Pre-University Physics, Book Chapter in Y.-J. Lee & A.-L. Tan (Eds.), Science education at the nexus of theory and practice (pp. 81-109). Rotterdam: Sense Publishers (2008).
Ho, S. Y.; Foong, S. K.; Lim, C. H.; Lim, C. C.; Lin, K.; Kuppan, L. Projectile motion on an inclined misty surface I: Capturing and analysing the trajectory, Phys. Educ. 44, 253-257 (2009).