One of the main motivation for building a quantum computer comes from the expected exponential gain in efficiency of certain quantum algorithms with respect to their classical counterparts. However, universal quantum computers of sufficient size are not available yet and quantum simulation can be an alternative. As a matter of fact, Feynman’s initial motivation for constructing a quantum computer was the efficient simulation of quantum dynamics. He proposed a universal quantum simulator consisting of a lattice of spins with nearest neighbor interactions that are freely specifiable and can efficiently reproduce the dynamics of any other many-particle quantum system with a finite-dimensional state space. Therefore, a universal quantum simulator is a controlled device that, operating itself at the quantum level, efficiently reproduces the dynamics of any other many-particle quantum system that evolves according to short range interactions.

Quantum simulation in Aspuru-Guzik research group focuses on developing digital and analog quantum simulators for quantum chemistry. Fully understanding the complicated electronic structures and molecules is one of the well-known challenges to quantum chemists. The aim of our group is to develop quantum algorithms and quantum simulators that can achieve significant advantages for the electronic-structure problems, the simulation of chemical dynamics, protein folding, photosynthetic systems, and other tasks. Although theory is still ahead of experiment, the research team collaborate actively with other groups to attain the experimental realization.

- Alán Aspuru-Guzik, Anthony D. Dutoi, Peter J. Love, and Martin Head-Gordon.
**Simulated Quantum Computation of Molecular Energies**.*Science*309, no. 5741 (September 9, 2005): 1704–1707. - Ivan Kassal, Stephen P. Jordan, Peter J. Love, Masoud Mohseni, and Alán Aspuru-Guzik.
**Polynomial-time Quantum Algorithm for the Simulation of Chemical Dynamics**.*Proceedings of the National Academy of Sciences*105, no. 48 (December 2, 2008): 18681 –18686. - B. P. Lanyon, J. D. Whitfield, G. G. Gillett, M. E. Goggin, M. P. Almeida, I. Kassal, J. D. Biamonte, et al.
**Towards Quantum Chemistry on a Quantum Computer**.*Nature Chemistry*2, no. 2 (January 10, 2010): 106–111. - Ivan Kassal, James D. Whitfield, Alejandro Perdomo-Ortiz, Man-Hong Yung, and Alán Aspuru-Guzik.
**Simulating Chemistry Using Quantum Computers**.*Annual Review of Physical Chemistry*62, no. 1 (May 5, 2011): 185–207. - Zhaokai Li, Man-Hong Yung, Hongwei Chen, Dawei Lu, James D. Whitfield, Xinhua Peng, Alán Aspuru-Guzik, and Jiangfeng Du.
**Solving Quantum Ground-State Problems with Nuclear Magnetic Resonance**.*Scientific Reports*1 (September 9, 2011). - Man-Hong Yung and Alán Aspuru-Guzik.
**A Quantum-quantum Metropolis Algorithm**.*Proceedings of the National Academy of Sciences*109, no. 3 (January 3, 2012): 754–759.