S. Saha

The spin $- 1/2$ chain with ferromagnetic exchange $J_{1} < 0$ between first neighbors and antiferromagnetic $J_{2} > 0$ between second neighbors supports two spin-Peierls (SP) instabili…

cond-mat.str-el2021★ 3 cited

Low temperature thermodynamics of the antiferromagnetic $J_{1} - J_{2}$ model: Entropy, critical points and spin gap

Sudip Kumar Saha, Manodip Routh, Manoranjan Kumar +1

The antiferromagnetic $J_{1} - J_{2}$ model is a spin-1/2 chain with isotropic exchange $J_{1} > 0$ between first neighbors and $J_{2} = α J_{1}$ between second neighbors. The model supports bo…

cond-mat.str-el2021★ 3 cited

Density matrix renormalization group approach to the low temperature thermodynamics of correlated 1D fermionic models

Sudip Kumar Saha, Debasmita Maiti, Manoranjan Kumar +1

The low temperature thermodynamics of correlated 1D fermionic models with spin and charge degrees of freedom is obtained by exact diagonalization (ED) of small systems and followed…

cond-mat.str-el2020★ 1 cited

Bond-bond correlations, gap relations and thermodynamics of spin- $1/2$ chains with spin-Peierls transitions and bond-order-wave phases

Sudip Kumar Saha, Manoranjan Kumar, Zoltán G. Soos

The spin- $1/2$ chain with antiferromagnetic exchange $J_{1}$ and $J_{2} = α J_{1}$ between first and second neighbors, respectively, has both gapless and gapped ( $Δ (α) > 0$ ) quantum phase…

cond-mat.str-el2020★ 15 cited

Modeling the spin-Peierls transition of spin- $1/2$ chains with correlated states: $J_{1} - J_{2}$ model, CuGeO $_{3}$ and TTF-CuS $_{4}$ C $_{4}$ (CF $_{3}$ ) $_{4}$

Sudip Kumar Saha, Monalisa Singh Roy, Manoranjan Kumar +1

The spin-Peierls transition at $T_{S P}$ of spin- $1/2$ chains with isotropic exchange interactions has previously been modeled as correlated for $T > T_{S P}$ and mean field for $T <…

cond-mat.str-el2019

Spin-Peierls transition of the dimer phase of the $J_{1} - J_{2}$ model: Energy cusp and CuGeO $_{3}$ thermodynamics

Sudip Kumar Saha, Manoranjan Kumar, Zoltán G. Soos

The spin-Peierls transition is modeled in the dimer phase of the spin- $1/2$ chain with exchanges $J_{1}$ , $J_{2} = α J_{1}$ between first and second neighbors. The degenerate ground state…

cond-mat.str-el2019

Hybrid ED/DMRG approach to the thermodynamics of 1D quantum models

Sudip Kumar Saha, Dayasindhu Dey, Manoranjan Kumar +1

Exact diagonalization (ED) of small model systems gives the thermodynamics of spin chains or quantum cell models at high temperature $T$ . Density matrix renormalization group (DMRG…

cond-mat.str-el2019★ 4 cited

Haldane and Dimer phases in a frustrated spin chain: an exact groundstate and associated topological phase transition

Shaon Sahoo, Dayasindhu Dey, Sudip Kumar Saha +1

A Heisenberg spin- $s$ chain with alternating ferromagnetic ( $- J_{1}^{F} < 0$ ) and antiferromagnetic ( $J_{1}^{A} > 0$ ) nearest-neighbor (NN) interactions, exhibits the Dimer and spin- $2 s$ Halda…

cond-mat.str-el2017

Characterization of Majorana-Ising phase transition in a helical liquid system

Sudip Kumar Saha, Dayasindhu Dey, Monalisa Singh Roy +2

We map an interacting helical liquid system, coupled to an external magnetic field and s-wave superconductor, to an XYZ spin system, and it undergoes Majorana-Ising transition by t…

cond-mat.str-el2017★ 3 cited

A Study of Topological Quantum Phase Transition and Majorana Localization Length for the Interacting Helical Liquid System

Dayasindhu Dey, Sudip Kumar Saha, P. Singha Deo +2

We consider a helical spin liquid system which shows majorana fermion modes at the edge. The interaction between the quasiparticles in this system induces phase transition, Majoran…

Spin Peierls transition of J1​−J2​ and extended models with ferromagnetic J1​.Sublattice dimerization and thermodynamics of zigzag chains in β-TeVO4​

Low temperature thermodynamics of the antiferromagnetic J1​−J2​ model: Entropy, critical points and spin gap

Density matrix renormalization group approach to the low temperature thermodynamics of correlated 1D fermionic models

Bond-bond correlations, gap relations and thermodynamics of spin-1/2 chains with spin-Peierls transitions and bond-order-wave phases

Modeling the spin-Peierls transition of spin-1/2 chains with correlated states: J1​−J2​ model, CuGeO3​ and TTF-CuS4​C4​(CF3​)4​

Spin-Peierls transition of the dimer phase of the J1​−J2​ model: Energy cusp and CuGeO3​ thermodynamics