Scaling of macroscopic superpositions close to a quantum phase transition

Abstract

It is well known that in a quantum phase transition (QPT), entanglement remains short ranged [Osterloh et al., Nature 416 608-610 (2005)]. We ask if there is a quantum property entailing the whole system which diverges near this point. Using the recently proposed measures of quantum macroscopisity, we show that near a quantum critical point, it is the effective size of macroscopic superposition between the two symmetry breaking states which grows to the scale of system size and its derivative with respect to the coupling shows both singular behavior and scaling properties.

The final version to appear in Physical Review B

References in corpus (9)

• Quantum Phase Transitions and Bipartite Entanglement
• Measuring multipartite entanglement via dynamic susceptibilities
• Quantum fidelity and quantum phase transitions in matrix product states
• Measures of macroscopicity for quantum spin systems
• Quantification of Macroscopic Quantum Superpositions within Phase Space
• A measurement-based measure of the size of macroscopic quantum superpositions
• Measuring the size of a Schroedinger cat state
• Entanglement and quantum phase transitions in matrix product spin one chains
• Is macroscopic entanglement a typical trait of many-particle quantum states?

Cited by in corpus (11)

• Shortcuts to adiabatic cat-state generation in bosonic Josephson junctions
• Quantum metrology with generalized cat states
• Exponential clustering of bipartite quantum entanglement at arbitrary temperatures
• Emergence of string-valence bond solid state in the frustrated $J_1-J_2$ transverse field Ising model on the square lattice
• Quantum macroscopicity measure for arbitrary spin systems and its application to quantum phase transitions
• Dynamics of coherence: Maximal quantum Fisher information vs. Loschmidt echo
• Fast generation of Cat states in Kerr nonlinear resonators via optimal adiabatic control
• Conversion of Thermal Equilibrium States into Superpositions of Macroscopically Distinct States
• Quantum coherence between subspaces: State transformation, Cohering Power, $k$-coherence and other properties
• Sequentially generated entanglement, macroscopicity and squeezing in a spin chain
• Critical slowing down of multi-atom entanglement by Rydberg blockade