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Quantum Phase Transition of Ground-state Entanglement in a Heisenberg Spin Chain Simulated in an NMR Quantum Computer

Xinhua Peng·Jiangfeng Du·Dieter Suter
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Abstract

Using an NMR quantum computer, we experimentally simulate the quantum phase transition of a Heisenberg spin chain. The Hamiltonian is generated by a multiple pulse sequence, the nuclear spin system is prepared in its (pseudo-pure) ground state and the effective Hamiltonian varied in such a way that the Heisenberg chain is taken from a product state to an entangled state and finally to a different product state.

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Xinhua Peng, Jiangfeng Du, Dieter Suter. 2004-11-08. Quantum Phase Transition of Ground-state Entanglement in a Heisenberg Spin Chain Simulated in an NMR Quantum Computer. https://doi.org/10.1103/physreva.71.012307

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