Visualization of superposition of macroscopically distinct states

Abstract

We propose a method of visualizing superpositions of macroscopically distinct states in many-body pure states. We introduce a visualization function, which is a coarse-grained quasi joint probability density for two or more hermitian additive operators. If a state contains superpositions of macroscopically distinct states, one can visualize them by plotting the visualization function for appropriately taken operators. We also explain how to efficiently find appropriate operators for a given state. As examples, we visualize four states containing superpositions of macroscopically distinct states: the ground state of the XY model, that of the Heisenberg antiferromagnet, a state in Shor's factoring algorithm, and a state in Grover's quantum search algorithm. Although the visualization function can take negative values, it becomes non-negative (hence becomes a coarse-grained joint probability density) if the characteristic width of the coarse-graining function used in the visualization function is sufficiently large.

12pages, 21figures

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Cited by in corpus (8)

• Shortcuts to adiabatic cat-state generation in bosonic Josephson junctions
• Strong entanglement causes low gate fidelity in inaccurate one-way quantum computation
• Fast generation of Cat states in Kerr nonlinear resonators via optimal adiabatic control
• Conversion of Thermal Equilibrium States into Superpositions of Macroscopically Distinct States
• Low-temperature coherence properties of Z_2 quantum memory
• Necessity of Superposition of Macroscopically Distinct States for Quantum Computational Speedup
• Macroscopic Schrödinger Cat Resistant to Particle Loss and Local Decoherence
• Superposition of Macroscopically Distinct States in Adiabatic Quantum Computation