Sequence of first-order quantum phase transitions in a frustrated spin half dimer-plaquette chain

TL;DR

This paper investigates a frustrated quantum spin chain with ferromagnetic bonds, revealing multiple first-order phase transitions, complex magnetization behaviors, and varying thermodynamic properties influenced by frustration levels.

Contribution

It uncovers the sequence of first-order quantum phase transitions and their effects on magnetization and thermodynamics in a frustrated spin chain with ferromagnetic bonds.

Findings

Magnetization exhibits plateaus and jumps depending on frustration.

Thermodynamics varies from spin-gap to Curie-like behavior with frustration.

Multiple first-order phase transitions are driven by frustration or magnetic field.

Abstract

We study the frustrated dimer-plaquette quantum spin chain for ferromagnetic dimer bonds. This quantum system undergoes a series of first-order ground-state phase transitions driven by frustration or by a magnetic field. We find that the different nature of the ground-state phases has a strong influence on the magnetization curve as well as the low-temperature thermodynamics. In particular, the magnetization curve exhibits plateaus and jumps, the number of which depends on the strength of frustration. The temperature dependence of the susceptibility may either show activated spin-gap behaviour for small frustration or Curie like paramagnetic behaviour for strong frustration.