Two- and three-dimensional random Ising models with a Gaussian distribution of couplings with variance J and nonvanishing mean value ${\mathrm{J}}_{0}$ are studied using the zero-temperature domain-wall renormalization group (DWRG). The DWRG trajectories in the ( ${\mathrm{J}}_{0}$ ,J) plane after rescaling can be collapsed on two curves: one for ${\mathrm{J}}_{0}$ /J> ${\mathrm{r}}_{\mathrm{c}}$ and the other for ${\mathrm{J}}_{0}$ /J ${\mathrm{r}}_{\mathrm{c}}$ . In the first case the DWRG flows are toward the ferromagnetic fixed point both in two and three dimensions while in the second case flows are towards a paramagnetic fixed point and spin-glass fixed point in two and three dimensions, respectively.Two- and three-dimensional random Ising models with a Gaussian distribution of couplings with variance J and nonvanishing mean value ${\mathrm{J}}_{0}$ are studied using the zero-temperature domain-wall renormalization group (DWRG). The DWRG trajectories in the (${\mathrm{J}}_{0}$,J) plane after rescaling can be collapsed on two curves: one for ${\mathrm{J}}_{0}$/J>${\mathrm{r}}_{\mathrm{c}}$ and the other for ${\mathrm{J}}_{0}$/J${\mathrm{r}}_{\mathrm{c}}$. In the first case the DWRG flows are toward the ferromagnetic fixed point both in two and three dimensions while in the second case flows are towards a paramagnetic fixed point and spin-glass fixed point in two and three dimensions, respectively.

arXiv:cond-mat/9609213Physical review. B, Condensed matterMay 1, 19973 citations

Renormalization group approach to spin glass systems

Giorgio Parisi A, Roberto Petronzio A, F. Rosati

arXiv:cond-mat/0101038The European Physical Journal BJun 1, 200117 citations

Domain wall renormalization group study of the XY model with quenched random phase shifts

Nobuhiko Akino, John Michael Kosterlitz

The $\mathrm{XY}$ model with quenched random disorder is studied by a zero-temperature domain wall renormalization group method in two dimensions (2D) and three dimensions (3D). Instead of the usual phase representation we use the charge (vortex) representation to compute the domain wall, or defect, energy. For the gauge glass corresponding to the maximum disorder we reconfirm earlier predictions that there is no ordered phase in 2D but an ordered phase can exist in 3D at low temperature. However, our simulations yield spin stiffness exponents ${\ensuremath{\theta}}_{s}\ensuremath{\approx}\ensuremath{-}0.36$ in 2D and ${\ensuremath{\theta}}_{s}\ensuremath{\approx}+0.31$ in 3D, which are considerably larger than previous estimates and strongly suggest that the lower critical dimension is less than three. For the $\ifmmode\pm\else\textpm\fi{}J \mathrm{XY}$ spin glass in 3D, we obtain a spin stiffness exponent ${\ensuremath{\theta}}_{s}\ensuremath{\approx}+0.10$ which supports the existence of spin glass order at finite temperature in contrast with previous estimates which obtain ${\ensuremath{\theta}}_{s}<0.$ Our method also allows us to study renormalization group flows of both the coupling constant and the disorder strength with a length scale L. Our results are consistent with recent analytic and numerical studies suggesting the absence of a reentrant transition in 2D at low temperature. Some possible consequences and connections with real vortex systems are discussed.The $\mathrm{XY}$ model with quenched random disorder is studied by a zero-temperature domain wall renormalization group method in two dimensions (2D) and three dimensions (3D). Instead of the usual phase representation we use the charge (vortex) representation to compute the domain wall, or defect, energy. For the gauge glass corresponding to the maximum disorder we reconfirm earlier predictions that there is no ordered phase in 2D but an ordered phase can exist in 3D at low temperature. However, our simulations yield spin stiffness exponents ${\ensuremath{\theta}}_{s}\ensuremath{\approx}\ensuremath{-}0.36$ in 2D and ${\ensuremath{\theta}}_{s}\ensuremath{\approx}+0.31$ in 3D, which are considerably larger than previous estimates and strongly suggest that the lower critical dimension is less than three. For the $\ifmmode\pm\else\textpm\fi{}J \mathrm{XY}$ spin glass in 3D, we obtain a spin stiffness exponent ${\ensuremath{\theta}}_{s}\ensuremath{\approx}+0.10$ which supports the existence of spin glass order at finite temperature in contrast with previous estimates which obtain ${\ensuremath{\theta}}_{s}<0.$ Our method also allows us to study renormalization group flows of both the coupling constant and the disorder strength with a length scale L. Our results are consistent with recent analytic and numerical studies suggesting the absence of a reentrant transition in 2D at low temperature. Some possible consequences and connections with real vortex systems are discussed.

arXiv:cond-mat/0203299Physical review. B, Condensed matterAug 29, 200235 citations

Domain walls for two-dimensional renormalization group flows

Davide Gaiotto A

arXiv:1201.0767Journal of High Energy PhysicsDec 1, 2012112 citations

Lower Critical Dimension of the XY Spin-Glass Model

J. Maucourt, Daniel R. Grempel

We investigate the $\mathrm{XY}$ spin-glass model in two and three dimensions using the domain-wall renormalization-group method. The results for systems of linear sizes up to $L\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}12$ (2D) and $L\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}8$ (3D) strongly suggest that the lower critical dimension for spin-glass ordering may be ${d}_{\mathrm{c}}\ensuremath{\approx}3$, rather than 4 as is commonly believed. Our 3D data favor the scenario of a low but finite spin-glass ordering temperature below the chiral transition, but they are also compatible with the system being at or slightly below its lower critical dimension.We investigate the $\mathrm{XY}$ spin-glass model in two and three dimensions using the domain-wall renormalization-group method. The results for systems of linear sizes up to $L\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}12$ (2D) and $L\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}8$ (3D) strongly suggest that the lower critical dimension for spin-glass ordering may be ${d}_{\mathrm{c}}\ensuremath{\approx}3$, rather than 4 as is commonly believed. Our 3D data favor the scenario of a low but finite spin-glass ordering temperature below the chiral transition, but they are also compatible with the system being at or slightly below its lower critical dimension.

arXiv:cond-mat/9709197Physical Review LettersJan 26, 199845 citations

Two- and three-dimensional random Ising models with a Gaussian distribution of couplings with variance J and nonvanishing mean value

{\mathrm{J}}_{0}

are studied using the zero-temperature domain-wall renormalization group (DWRG). The DWRG trajectories in the (

{\mathrm{J}}_{0}

,J) plane after rescaling can be collapsed on two curves: one for

{\mathrm{J}}_{0}

/J>

{\mathrm{r}}_{\mathrm{c}}

and the other for

{\mathrm{J}}_{0}

{\mathrm{r}}_{\mathrm{c}}

. In the first case the DWRG flows are toward the ferromagnetic fixed point both in two and three dimensions while in the second case flows are towards a paramagnetic fixed point and spin-glass fixed point in two and three dimensions, respectively.

The

\mathrm{XY}

model with quenched random disorder is studied by a zero-temperature domain wall renormalization group method in two dimensions (2D) and three dimensions (3D). Instead of the usual phase representation we use the charge (vortex) representation to compute the domain wall, or defect, energy. For the gauge glass corresponding to the maximum disorder we reconfirm earlier predictions that there is no ordered phase in 2D but an ordered phase can exist in 3D at low temperature. However, our simulations yield spin stiffness exponents ${\ensuremath{\theta}}_{s}\ensuremath{\approx}\ensuremath{-}0.36$ in 2D and ${\ensuremath{\theta}}_{s}\ensuremath{\approx}+0.31$ in 3D, which are considerably larger than previous estimates and strongly suggest that the lower critical dimension is less than three. For the $\ifmmode\pm\else\textpm\fi{}J \mathrm{XY}$ spin glass in 3D, we obtain a spin stiffness exponent ${\ensuremath{\theta}}_{s}\ensuremath{\approx}+0.10$ which supports the existence of spin glass order at finite temperature in contrast with previous estimates which obtain ${\ensuremath{\theta}}_{s}<0.$ Our method also allows us to study renormalization group flows of both the coupling constant and the disorder strength with a length scale L. Our results are consistent with recent analytic and numerical studies suggesting the absence of a reentrant transition in 2D at low temperature. Some possible consequences and connections with real vortex systems are discussed.

We investigate the

\mathrm{XY}

spin-glass model in two and three dimensions using the domain-wall renormalization-group method. The results for systems of linear sizes up to

L\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}12

(2D) and

L\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}8

(3D) strongly suggest that the lower critical dimension for spin-glass ordering may be ${d}_{\mathrm{c}}\ensuremath{\approx}3$, rather than 4 as is commonly believed. Our 3D data favor the scenario of a low but finite spin-glass ordering temperature below the chiral transition, but they are also compatible with the system being at or slightly below its lower critical dimension.