Europhysics Letters (EPL)

Finite-Size Scaling for the Two-Dimensional Frustrated Quantum Heisenberg Antiferromagnet

Heinz J. Schulz, Timothy A. L. Ziman

Published Feb 21, 1992• 211 citations

Abstract

Using results for the 4 × 4 and 6 × 6 lattice, we produce the first finite-size scaling analysis of the frustrated Heisenberg model in two dimensions. The results indicate a continuous phase transition from the ordered phase into an intermediate phase without long-range magnetic order, as for the (2 + 1)-dimensional nonlinear sigma-model. The intermediate phase is stable for 0.4 < J2/J1 < 0.65 and exhibits either dimerization or broken chiral symmetry. The transition to the collinear phase at J2/J1 0.65 is apparently of first order.

DOI: 10.1209/0295-5075/18/4/013

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Ground-state phases of the frustrated spin- 12 J1 – J2 – J3 Heisenberg ferromagnet ( J1<0 ) on the honeycomb lattice with J3=J2>0

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Europhysics Letters (EPL)

Finite-Size Scaling for the Two-Dimensional Frustrated Quantum Heisenberg Antiferromagnet

Heinz J. Schulz, Timothy A. L. Ziman

Published Feb 21, 1992• 211 citations

Publisher

Abstract

DOI: 10.1209/0295-5075/18/4/013

Related papers

Quantum phase transitions in the two-dimensional J1−J2 model

Oleg P. Sushkov, J. Oitmaa, Zheng Weihong

We analyze the phase diagram of the frustrated Heisenberg antiferromagnet, the ${J}_{1}{\ensuremath{-}J}_{2}$ model, in two dimensions. Two quantum phase transitions in the model are already known: the second-order transition from the N\'eel state to the spin liquid state at ${(J}_{2}{/J}_{1}{)}_{c2}\ensuremath{\approx}0.38,$ and the first-order transition from the spin liquid state to the collinear state at ${(J}_{2}{/J}_{1}{)}_{c4}\ensuremath{\approx}0.60.$ We have found evidence for two second-order phase transitions: the transition from the spin columnar dimerized state to the state with plaquette-type modulation at ${(J}_{2}{/J}_{1}{)}_{c3}=0.50\ifmmode\pm\else\textpm\fi{}0.02,$ and the transition from the simple N\'eel state to the N\'eel state with spin columnar dimerization at ${(J}_{2}{/J}_{1}{)}_{c1}=0.34\ifmmode\pm\else\textpm\fi{}0.04.$ We also present an independent calculation of ${(J}_{2}{/J}_{1}{)}_{c2}\ensuremath{\approx}0.38$ using another approach.We analyze the phase diagram of the frustrated Heisenberg antiferromagnet, the ${J}_{1}{\ensuremath{-}J}_{2}$ model, in two dimensions. Two quantum phase transitions in the model are already known: the second-order transition from the N\'eel state to the spin liquid state at ${(J}_{2}{/J}_{1}{)}_{c2}\ensuremath{\approx}0.38,$ and the first-order transition from the spin liquid state to the collinear state at ${(J}_{2}{/J}_{1}{)}_{c4}\ensuremath{\approx}0.60.$ We have found evidence for two second-order phase transitions: the transition from the spin columnar dimerized state to the state with plaquette-type modulation at ${(J}_{2}{/J}_{1}{)}_{c3}=0.50\ifmmode\pm\else\textpm\fi{}0.02,$ and the transition from the simple N\'eel state to the N\'eel state with spin columnar dimerization at ${(J}_{2}{/J}_{1}{)}_{c1}=0.34\ifmmode\pm\else\textpm\fi{}0.04.$ We also present an independent calculation of ${(J}_{2}{/J}_{1}{)}_{c2}\ensuremath{\approx}0.38$ using another approach.

arXiv:cond-mat/0007329Physical review. B, Condensed matterFeb 20, 2001151 citations

Ground-state phases of the frustrated spin- 12 J1 – J2 – J3 Heisenberg ferromagnet ( J1<0 ) on the honeycomb lattice with J3=J2>0

P. H. Y. Li, R. F. Bishop, DAMIAN J. J. FARNELL +2 more

We study the ground-state (GS) properties of the frustrated spin- $\frac{1}{2}$ ${J}_{1}$ -- ${J}_{2}$ -- ${J}_{3}$ Heisenberg model on the two-dimensional honeycomb lattice with ferromagnetic nearest-neighbor (${J}_{1}=\ensuremath{-}1$) exchange and frustrating antiferromagnetic next-nearest-neighbor ( ${J}_{2}>0$ ) and next-next-nearest-neighbor ( ${J}_{3}>0$ ) exchanges, for the case ${J}_{3}={J}_{2}$ . We use the coupled-cluster method implemented to high orders of approximation, complemented by the Lanczos exact diagonalization of a large finite lattice with 32 sites, in order to calculate the GS energy, magnetic order parameter, and spin-spin correlation functions. In one scenario we find a quantum phase transition point between regions characterized by ferromagnetic order and a form of antiferromagnetic (``striped'') collinear order at ${J}_{2}^{c}\ensuremath{\approx}0.1095\ifmmode\pm\else\textpm\fi{}0.0005$, which is below the corresponding hypothetical transition point at ${J}_{2}^{\mathrm{cl}}=\frac{1}{7}$ ($\ensuremath{\approx}0.143$) for the classical version of the model, in which we momentarily ignore the intervening noncollinear spiral phase in the region $\frac{1}{10}<{J}_{2}<\frac{1}{5}$ . Hence we see that quantum fluctuations appear to stabilize somewhat the collinear antiferromagnetic order in preference to the ferromagnetic order in this model. We compare results for the present ferromagnetic case (with ${J}_{1}=\ensuremath{-}1$) to previous results for the corresponding antiferromagnetic case (with ${J}_{1}=+1$ ). The magnetic order parameter is found to behave similarly for the ferromagnetic and the antiferromagnetic models for large values of the frustration parameter ${J}_{2}$ . However, there are considerable differences in the behavior of the order parameters for the two models for ${J}_{2}/|{J}_{1}|\ensuremath{\lesssim}0.6$. For example, the quasiclassical collinear magnetic long-range order for the antiferromagnetic model (with ${J}_{1}=+1$ ) breaks down at ${J}_{2}^{{c}_{2}}\ensuremath{\approx}0.60$, whereas the ``equivalent'' point for the ferromagnetic model (with ${J}_{1}=\ensuremath{-}1$) occurs at ${J}_{2}^{c}\ensuremath{\approx}0.11$. Unlike in the antiferromagnetic model (with ${J}_{1}=+1$ ), where a plaquette valence-bond crystal phase intrudes between the two corresponding quasiclassical antiferromagnetic phases (with N\'eel and striped order) for ${J}_{2}^{{c}_{1}}<{J}_{2}<{J}_{2}^{{c}_{2}}$ , with ${J}_{2}^{{c}_{1}}\ensuremath{\approx}0.47$, we find no clear indications at all in the ferromagnetic model for an intermediate magnetically disordered phase between the corresponding phases exhibiting ferromagnetic and striped order. Instead the evidence for the ferromagnetic model (with ${J}_{1}=\ensuremath{-}1$) points to one of two scenarios: either there is a direct first-order transition between the two magnetically ordered phases, as mentioned above; or there exists an intervening phase between them in the very narrow range $0.10\ensuremath{\lesssim}{J}_{2}\ensuremath{\lesssim}0.12$, which is probably a remnant of the spiral phase that exists in the classical counterpart of the model over the larger range $\frac{1}{10}<{J}_{2}<\frac{1}{5}$ .We study the ground-state (GS) properties of the frustrated spin-$\frac{1}{2}$ ${J}_{1}$--${J}_{2}$--${J}_{3}$ Heisenberg model on the two-dimensional honeycomb lattice with ferromagnetic nearest-neighbor (${J}_{1}=\ensuremath{-}1$) exchange and frustrating antiferromagnetic next-nearest-neighbor (${J}_{2}>0$) and next-next-nearest-neighbor (${J}_{3}>0$) exchanges, for the case ${J}_{3}={J}_{2}$. We use the coupled-cluster method implemented to high orders of approximation, complemented by the Lanczos exact diagonalization of a large finite lattice with 32 sites, in order to calculate the GS energy, magnetic order parameter, and spin-spin correlation functions. In one scenario we find a quantum phase transition point between regions characterized by ferromagnetic order and a form of antiferromagnetic (``striped'') collinear order at ${J}_{2}^{c}\ensuremath{\approx}0.1095\ifmmode\pm\else\textpm\fi{}0.0005$, which is below the corresponding hypothetical transition point at ${J}_{2}^{\mathrm{cl}}=\frac{1}{7}$ ($\ensuremath{\approx}0.143$) for the classical version of the model, in which we momentarily ignore the intervening noncollinear spiral phase in the region $\frac{1}{10}<{J}_{2}<\frac{1}{5}$. Hence we see that quantum fluctuations appear to stabilize somewhat the collinear antiferromagnetic order in preference to the ferromagnetic order in this model. We compare results for the present ferromagnetic case (with ${J}_{1}=\ensuremath{-}1$) to previous results for the corresponding antiferromagnetic case (with ${J}_{1}=+1$). The magnetic order parameter is found to behave similarly for the ferromagnetic and the antiferromagnetic models for large values of the frustration parameter ${J}_{2}$. However, there are considerable differences in the behavior of the order parameters for the two models for ${J}_{2}/|{J}_{1}|\ensuremath{\lesssim}0.6$. For example, the quasiclassical collinear magnetic long-range order for the antiferromagnetic model (with ${J}_{1}=+1$) breaks down at ${J}_{2}^{{c}_{2}}\ensuremath{\approx}0.60$, whereas the ``equivalent'' point for the ferromagnetic model (with ${J}_{1}=\ensuremath{-}1$) occurs at ${J}_{2}^{c}\ensuremath{\approx}0.11$. 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Instead the evidence for the ferromagnetic model (with ${J}_{1}=\ensuremath{-}1$) points to one of two scenarios: either there is a direct first-order transition between the two magnetically ordered phases, as mentioned above; or there exists an intervening phase between them in the very narrow range $0.10\ensuremath{\lesssim}{J}_{2}\ensuremath{\lesssim}0.12$, which is probably a remnant of the spiral phase that exists in the classical counterpart of the model over the larger range $\frac{1}{10}<{J}_{2}<\frac{1}{5}$.

arXiv:1109.6229Physical Review BFeb 21, 201231 citations

Series expansion studies of the J 1 − J 2 Heisenberg bilayer

Erik Wagner, Wolfram Brenig

We study a bilayer of the frustrated ${J}_{1}\text{\ensuremath{-}}{J}_{2}$ Heisenberg model on the square lattice. Starting from the dimer limit at strong interlayer coupling, we perform series expansions using the perturbative continuous unitary transformation, based on the flow equation method, in order to determine the spectrum up to the two-triplon sector. From the one-triplon dispersion, we obtain quantum critical lines for transitions from the dimer phase into either N\'eel or collinear magnetic order. For low to intermediate frustration these transitions are consistent with existing findings, based on the magnetic phases. In the region of strongest frustration, i.e., ${J}_{2}/{J}_{1}\ensuremath{\sim}0.5$, we provide an estimate for the stability of the anticipated single-layer quantum spin-liquids against finite interlayer coupling. In the two-triplon sector, we find a set of well defined (anti)bound states, which can be classified according to total spin and in-plane rotational symmetry. For vanishing frustration, these states agree with the previous series expansion analysis. For ${J}_{2}/{J}_{1}\ensuremath{\gtrsim}0.5$, we provide evidence for a close-by condensation of one-triplon and two-triplon singlet bound states, suggesting that between the dimer and the collinear state additional phases may intervene.We study a bilayer of the frustrated ${J}_{1}\text{\ensuremath{-}}{J}_{2}$ Heisenberg model on the square lattice. Starting from the dimer limit at strong interlayer coupling, we perform series expansions using the perturbative continuous unitary transformation, based on the flow equation method, in order to determine the spectrum up to the two-triplon sector. From the one-triplon dispersion, we obtain quantum critical lines for transitions from the dimer phase into either N\'eel or collinear magnetic order. For low to intermediate frustration these transitions are consistent with existing findings, based on the magnetic phases. In the region of strongest frustration, i.e., ${J}_{2}/{J}_{1}\ensuremath{\sim}0.5$, we provide an estimate for the stability of the anticipated single-layer quantum spin-liquids against finite interlayer coupling. In the two-triplon sector, we find a set of well defined (anti)bound states, which can be classified according to total spin and in-plane rotational symmetry. For vanishing frustration, these states agree with the previous series expansion analysis. For ${J}_{2}/{J}_{1}\ensuremath{\gtrsim}0.5$, we provide evidence for a close-by condensation of one-triplon and two-triplon singlet bound states, suggesting that between the dimer and the collinear state additional phases may intervene.

Physical review. B./Physical review. BSep 14, 20230 citations

Series expansion studies of the $J_1$ - $J_2$ -Heisenberg bilayerSeries expansion studies of the $J_1$-$J_2$-Heisenberg bilayer

Wagner, Erik, Wolfram Brenig

We study a bilayer of the frustrated $J_1$ - $J_2$ Heisenberg-model on the square lattice. Starting from the dimer limit at strong interlayer coupling, we perform series expansions using the perturbative Continuous Unitary Transformation, based on the flow equation method, in order to determine the spectrum up to the two-triplon sector. From the one-triplon dispersion we obtain quantum critical lines for transitions from the dimer phase into either Néel or collinear magnetic order. For low to intermediate frustration these transitions are consistent with existing findings, based on the magnetic phases. In the region of strongest frustration, i.e. $J_2/J_1\sim 0.5$ , we provide an estimate for the stability of the anticipated single-layer quantum spin-liquids against finite interlayer coupling. In the two-triplon sector we find a set of well defined (anti)bound states, which can be classified according to total spin and in-plane rotational symmetry. For vanishing frustration these states agree with previous series expansion analysis. For $J_2/J_1\gtrsim 0.5$ we provide evidence for a close-by condensation of one-triplon and two-triplon singlet bound states, suggesting that between the dimer and the collinear state, additional phases may intervene.We study a bilayer of the frustrated $J_1$-$J_2$ Heisenberg-model on the square lattice. Starting from the dimer limit at strong interlayer coupling, we perform series expansions using the perturbative Continuous Unitary Transformation, based on the flow equation method, in order to determine the spectrum up to the two-triplon sector. From the one-triplon dispersion we obtain quantum critical lines for transitions from the dimer phase into either Néel or collinear magnetic order. For low to intermediate frustration these transitions are consistent with existing findings, based on the magnetic phases. In the region of strongest frustration, i.e. $J_2/J_1\sim 0.5$, we provide an estimate for the stability of the anticipated single-layer quantum spin-liquids against finite interlayer coupling. In the two-triplon sector we find a set of well defined (anti)bound states, which can be classified according to total spin and in-plane rotational symmetry. For vanishing frustration these states agree with previous series expansion analysis. For $J_2/J_1\gtrsim 0.5$ we provide evidence for a close-by condensation of one-triplon and two-triplon singlet bound states, suggesting that between the dimer and the collinear state, additional phases may intervene.

arXiv:2302.11599Feb 22, 20230 citations

J1−J2 frustrated two-dimensional Heisenberg model: Random phase approximation and functional renormalization group

Johannes Reuther, P. Wölfle

We study the ground-state properties of the two-dimensional spin-1/2 ${J}_{1}\text{\ensuremath{-}}{J}_{2}$ Heisenberg model on a square lattice, within diagrammatic approximations using an auxiliary-fermion formulation with exact projection. In a first approximation, we assume a phenomenological width of the pseudofermion spectral function to calculate the magnetization, susceptibilities, and the spin-correlation length within random-phase approximation, demonstrating the appearance of a paramagnetic phase between the N\'eel-ordered and Collinear-ordered phases, at sufficiently large pseudofermion damping. Second we use a functional renormalization-group formulation. We find that the conventional truncation scheme omitting three-particle and higher-order vertices is not sufficient. We therefore include self-energy renormalizations in the single-scale propagator as recently proposed by Katanin, to preserve Ward identities in a better way. We find N\'eel order at $g={J}_{2}/{J}_{1}\ensuremath{\lesssim}{g}_{\text{c}1}\ensuremath{\approx}0.4\dots{}0.45$ and Collinear order at $g\ensuremath{\gtrsim}{g}_{\text{c}2}\ensuremath{\approx}0.66\dots{}0.68$, which is in good agreement with results obtained by numerical studies. In the intervening quantum paramagnetic phase, we find enhanced columnar dimer and plaquette fluctuations of equal strength.We study the ground-state properties of the two-dimensional spin-1/2 ${J}_{1}\text{\ensuremath{-}}{J}_{2}$ Heisenberg model on a square lattice, within diagrammatic approximations using an auxiliary-fermion formulation with exact projection. In a first approximation, we assume a phenomenological width of the pseudofermion spectral function to calculate the magnetization, susceptibilities, and the spin-correlation length within random-phase approximation, demonstrating the appearance of a paramagnetic phase between the N\'eel-ordered and Collinear-ordered phases, at sufficiently large pseudofermion damping. Second we use a functional renormalization-group formulation. We find that the conventional truncation scheme omitting three-particle and higher-order vertices is not sufficient. We therefore include self-energy renormalizations in the single-scale propagator as recently proposed by Katanin, to preserve Ward identities in a better way. We find N\'eel order at $g={J}_{2}/{J}_{1}\ensuremath{\lesssim}{g}_{\text{c}1}\ensuremath{\approx}0.4\dots{}0.45$ and Collinear order at $g\ensuremath{\gtrsim}{g}_{\text{c}2}\ensuremath{\approx}0.66\dots{}0.68$, which is in good agreement with results obtained by numerical studies. In the intervening quantum paramagnetic phase, we find enhanced columnar dimer and plaquette fluctuations of equal strength.

arXiv:0912.0860Physical Review BApr 8, 2010161 citations

Order-parameter fluctuations in the frustrated Heisenberg model on the square lattice

Shu Zhang, Gerhard H. Muller

The T=0 dynamics of the two-dimensional s=1/2 Heisenberg model with competing nearest-neighbor (J1) and next-nearest-neighbor (J2) interactions is explored via the recursion method, specifically the frequency-dependent fluctuations of the order parameters associated with some of the known or suspected ordering tendencies in this system, i.e., Néel, collinear, dimer, and chiral order. The results for the dynamic structure factors of the respective fluctuation operators show a strong indication of collinear order at J2/J1≳0.6 and a potential for dimer order at 0.5≲J2/J1≲0.6, whereas the chiral ordering tendency is observed to be considerably weaker.The T=0 dynamics of the two-dimensional s=1/2 Heisenberg model with competing nearest-neighbor (J1) and next-nearest-neighbor (J2) interactions is explored via the recursion method, specifically the frequency-dependent fluctuations of the order parameters associated with some of the known or suspected ordering tendencies in this system, i.e., Néel, collinear, dimer, and chiral order. The results for the dynamic structure factors of the respective fluctuation operators show a strong indication of collinear order at J2/J1≳0.6 and a potential for dimer order at 0.5≲J2/J1≲0.6, whereas the chiral ordering tendency is observed to be considerably weaker.

arXiv:cond-mat/9508145Journal of Applied PhysicsApr 15, 19960 citations

We study the ground-state (GS) properties of the frustrated spin-

\frac{1}{2}

{J}_{1}

{J}_{2}

{J}_{3}

Heisenberg model on the two-dimensional honeycomb lattice with ferromagnetic nearest-neighbor (${J}_{1}=\ensuremath{-}1$) exchange and frustrating antiferromagnetic next-nearest-neighbor (

{J}_{2}>0

) and next-next-nearest-neighbor (

{J}_{3}>0

) exchanges, for the case

{J}_{3}={J}_{2}

. We use the coupled-cluster method implemented to high orders of approximation, complemented by the Lanczos exact diagonalization of a large finite lattice with 32 sites, in order to calculate the GS energy, magnetic order parameter, and spin-spin correlation functions. In one scenario we find a quantum phase transition point between regions characterized by ferromagnetic order and a form of antiferromagnetic (``striped'') collinear order at ${J}_{2}^{c}\ensuremath{\approx}0.1095\ifmmode\pm\else\textpm\fi{}0.0005$, which is below the corresponding hypothetical transition point at

{J}_{2}^{\mathrm{cl}}=\frac{1}{7}

($\ensuremath{\approx}0.143$) for the classical version of the model, in which we momentarily ignore the intervening noncollinear spiral phase in the region

\frac{1}{10}<{J}_{2}<\frac{1}{5}

. Hence we see that quantum fluctuations appear to stabilize somewhat the collinear antiferromagnetic order in preference to the ferromagnetic order in this model. We compare results for the present ferromagnetic case (with ${J}_{1}=\ensuremath{-}1$) to previous results for the corresponding antiferromagnetic case (with

{J}_{1}=+1

). The magnetic order parameter is found to behave similarly for the ferromagnetic and the antiferromagnetic models for large values of the frustration parameter

{J}_{2}

. However, there are considerable differences in the behavior of the order parameters for the two models for ${J}_{2}/|{J}_{1}|\ensuremath{\lesssim}0.6$. For example, the quasiclassical collinear magnetic long-range order for the antiferromagnetic model (with

{J}_{1}=+1

) breaks down at ${J}_{2}^{{c}_{2}}\ensuremath{\approx}0.60$, whereas the ``equivalent'' point for the ferromagnetic model (with ${J}_{1}=\ensuremath{-}1$) occurs at ${J}_{2}^{c}\ensuremath{\approx}0.11$. Unlike in the antiferromagnetic model (with

{J}_{1}=+1

), where a plaquette valence-bond crystal phase intrudes between the two corresponding quasiclassical antiferromagnetic phases (with N\'eel and striped order) for

{J}_{2}^{{c}_{1}}<{J}_{2}<{J}_{2}^{{c}_{2}}

, with ${J}_{2}^{{c}_{1}}\ensuremath{\approx}0.47$, we find no clear indications at all in the ferromagnetic model for an intermediate magnetically disordered phase between the corresponding phases exhibiting ferromagnetic and striped order. Instead the evidence for the ferromagnetic model (with ${J}_{1}=\ensuremath{-}1$) points to one of two scenarios: either there is a direct first-order transition between the two magnetically ordered phases, as mentioned above; or there exists an intervening phase between them in the very narrow range $0.10\ensuremath{\lesssim}{J}_{2}\ensuremath{\lesssim}0.12$, which is probably a remnant of the spiral phase that exists in the classical counterpart of the model over the larger range

\frac{1}{10}<{J}_{2}<\frac{1}{5}

Series expansion studies of the

J_1

J_2

-Heisenberg bilayer

We study a bilayer of the frustrated

J_1

J_2

Heisenberg-model on the square lattice. Starting from the dimer limit at strong interlayer coupling, we perform series expansions using the perturbative Continuous Unitary Transformation, based on the flow equation method, in order to determine the spectrum up to the two-triplon sector. From the one-triplon dispersion we obtain quantum critical lines for transitions from the dimer phase into either Néel or collinear magnetic order. For low to intermediate frustration these transitions are consistent with existing findings, based on the magnetic phases. In the region of strongest frustration, i.e.

J_2/J_1\sim 0.5

, we provide an estimate for the stability of the anticipated single-layer quantum spin-liquids against finite interlayer coupling. In the two-triplon sector we find a set of well defined (anti)bound states, which can be classified according to total spin and in-plane rotational symmetry. For vanishing frustration these states agree with previous series expansion analysis. For

J_2/J_1\gtrsim 0.5

we provide evidence for a close-by condensation of one-triplon and two-triplon singlet bound states, suggesting that between the dimer and the collinear state, additional phases may intervene.