Bose-Einstein condensation and entanglement in magnetic systems

Abstract

We present a study of magnetic field induced quantum phase transitions in insulating systems. A generalized scaling theory is used to obtain the temperature dependence of several physical quantities along the quantum critical trajectory ($H=H_C$, $T\to 0$) where $H$ is a longitudinal external magnetic field and $H_C$ the critical value at which the transition occurs. We consider transitions from a spin liquid at a critical field $H_{C1}$ and from a fully polarized paramagnet, at $H_{C2}$, into phases with long range order in the transverse components. The transitions at $H_{C1}$ and $H_{C2}$ can be viewed as Bose-Einstein condensations of magnons which however belong to different universality classes since they have different values of the dynamic critical exponent $z$. Finally, we use that the magnetic susceptibility is an entanglement witness to discuss how this type of correlation sets in as the system approaches the quantum critical point along the critical trajectory, $H=H_{C2}$, $T\to 0$.

7 pages, 1 Table; accepted version; changes in text and new references

References in corpus (18)

• The break up of heavy electrons at a quantum critical point
• Realization of Bose-Einstein condensation of dilute magnons in TlCuCl${}_3$
• Violation of local uncertainty relations as a signature of entanglement
• Diverging Entanglement Length in Gapped Quantum Spin Systems
• Field-Induced Quantum Critical Point in CeCoIn5
• Dimensional reduction at a quantum critical point
• Bose-Einstein Condensation of S = 1 Ni spin degrees of freedom in NiCl2-4SC(NH2)2
• Magnetic Susceptibility as a Macrosopic Entaglement Witness
• Bose-Einstein Condensation of Magnons in Cs2CuCl4
• Entanglement and factorized ground states in two-dimensional quantum antiferromagnets
• Magnetic Field Induced Non-Fermi-Liquid Behavior in YbAgGe Single Crystal
• Field-Tuned Quantum Critical Point in CeCoIn${}_5$ Near the Superconducting Upper Critical Field
• Sound attenuation on the Bose-Einstein condensation of magnons in TlCuCl_3
• Quantum Phase Transitions in Coupled Dimer Compounds
• Quantum Critical Point of the XY Model and Condensation of Field-Induced Quasiparticles in Dimer Compounds
• Some basic aspects of quantum phase transitions
• Field-tuned quantum critical point of antiferromagnetic metals
• Field-induced Bose-Einstein condensation of interacting dilute magnons in three-dimensional spin systems: A renormalization-group study

Cited by in corpus (4)

• Thermal entanglement of one-dimensional Heisenberg quantum spin chains in magnetic fields
• Bose-Einstein condensation in antiferromagnets close to the saturation field
• Interplay of quantum and classical fluctuations near quantum critical points
• Fluctuations in a superconducting quantum critical point of multi-band metals