Quantum phase diagram of a frustrated spin- 12 system on a trellis ladder

Abstract

We study an isotropic Heisenberg spin-1/2 model on a trellis ladder which is composed of two J1 − J2 zigzag ladders interacting through anti-ferromagnetic rung couplings J3. The J1 and J2 are ferromagnetic zigzag spin interaction between two legs and anti-ferromagnetic interaction along each leg of a zigzag ladder. A quantum phase diagram of this model is constructed using the density matrix renormalization group (DMRG) method and linearized spin wave analysis. In small J2 limit a short range stripe collinear phase is found in the presence of J3, whereas, in the large J2/J3 limit non-collinear quasi-long range phase is found. The system shows a short range non-collinear state in large J3 limit. The short range order phase is the dominant feature of this phase diagram. We also show that the results obtained by DMRG and linearized spin wave analysis show similar phase boundary between stripe collinear and non-collinear short range phases, and the collinear phase region shrinks with increasing J3. We apply this model to understand the magnetic properties of CaV2O5 and also fit the experimental data of susceptibility and magnetization. The variation of magnetic specific heat capacity as function of external magnetic field is also predicted. We note that J3 is a dominant interaction in this system, whereas J1 and J2 are approximately half of J3.

Quantum phases of ferromagnetically coupled dimers on Shastry-Sutherland lattice

“…In a geometrically frustrated system wavevector or the pitch angle of a non-collinear spin ordering, in general, depends on the competing exchange interactions [60][61][62] and therefore, it is important to understand behaviour of pitch angle θ in various exchange interaction limits to quantify spin modulation in terms of the pitch angle Q x and Q y . Fig.…”

Machine learning approach to study quantum phase transitions of a frustrated one dimensional spin-1/2 system

“…interesting in presence of many-body interactions [11][12][13][14][15][16][17]. These correlated model systems are important and relevant for modeling the real materials and have exotic phases in the ground state (GS), but solving even the simplest correlated model Hamiltonian is extremely difficult due to a large number of coupled degrees of freedom [3][4][5].…”

Quantum phases and thermodynamics of a frustrated spin-1/2 ladder with alternate Ising–Heisenberg rung interactions

“…Frustrated low-dimensional quantum magnets exhibit a zoo of quantum phases which attracts more interest to both theoreticians as well as experimentalists, and so the theoretical studies are quite necessary for the verification of the experimental results due to the ever-growing synthesis of low-dimensional magnetic materials [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15]. In the spin chains and ladder systems, the competing exchange interactions lead to many interesting quantum phases like ferromagnetic ground state [16], Néel phase [17][18][19], Luttinger liquid [20,21], spiral [22], spin liquid [23,24], dimer phase [4], etc. The ground state (GS) of antiferromagnetic isotropic Heisenberg spin-1/2 zigzag chain has a gapless spectrum in small or strong coupling limit, whereas, it has a gapped spectrum for the moderate value of the ratio of the exchange interactions [25][26][27][28][29][30].…”

“…antiferromagnet Heisenberg spin-1/2 on a triangular lattice [36,37] or exchange interaction driven frustration such as 1D spin-1/2 system interacting with nearest neighbor interaction J 1 and antiferromagnetic next nearest neighbor exchange interaction J 2 [12,13,15,17,[38][39][40]. Frustrated model Hamiltonians of one dimensional systems and zigzag geometry [41,42] are extensively studied theoretically and GS of these systems have exotic phases like spin liquid [3,43], dimer [11,[13][14][15][16][17][18][19], spiral/non-collinear spin phase [11,14,44], ferromagnetic phase etc.…”