scholarly journals Slowing down of spin glass correlation length growth: Simulations meet experiments

2019 ◽  
Vol 100 (9) ◽  
Author(s):  
Qiang Zhai ◽  
V. Martin-Mayor ◽  
Deborah L. Schlagel ◽  
Gregory G. Kenning ◽  
Raymond L. Orbach
Keyword(s):  
Spin Glass ◽  
Correlation Length ◽  
Slowing Down ◽  
Length Growth

NMR-NQR Study of the Crossover from the Spin-Glass to the Superconducting Phase in La2-xSrxCuO4

1999 ◽  
Vol 13 (09n10) ◽  
pp. 1235-1240
Author(s):  
M.-H. Julien ◽  
P. Carretta ◽  
F. Borsa ◽  
A. Rigamonti
Keyword(s):  
Low Temperature ◽  
Spin Glass ◽  
Correlation Length ◽  
Superconducting Phase ◽  
Spin Fluctuations ◽  
Relaxation Rates ◽  
Slowing Down ◽  
Spin Glass Behavior ◽  
Spin Freezing ◽  
Glass Behavior

139 La and 63 Cu NQR relaxation rates are used to obtain insights on the effects of itinerant holes on the magnetic in-plane correlation length, for x ≤ 0.04 in La 2-x Sr x CuO 4. For these concentrations, corresponding to spin-glass behavior at low temperature, evidence for the microsegregation of holes along stripes is presented. Preliminary relaxation results for an amount of Sr doping leading to superconductivity are also presented and discussed in terms of the crossover from the spin-glass to the underdoped superconducting regime: for x = 0.06 a slowing down of spin fluctuations is evidenced and superconductivity is found to coexist with spin-freezing.

scholarly journals Assessing the role of static length scales behind glassy dynamics in polydisperse hard disks

2015 ◽  
Vol 112 (22) ◽  
pp. 6920-6924 ◽  
Author(s):  
John Russo ◽  
Hajime Tanaka
Keyword(s):  
Correlation Length ◽  
Hard Disk ◽  
Decay Length ◽  
Hard Disks ◽  
Dynamic Heterogeneity ◽  
Disk System ◽  
Slowing Down ◽  
Static Correlation ◽  
Dynamic Length

The possible role of growing static order in the dynamical slowing down toward the glass transition has recently attracted considerable attention. On the basis of random first-order transition theory, a new method to measure the static correlation length of amorphous order, called “point-to-set” (PTS) length, has been proposed and used to show that the dynamic length grows much faster than the static length. Here, we study the nature of the PTS length, using a polydisperse hard-disk system, which is a model that is known to exhibit a growing hexatic order upon densification. We show that the PTS correlation length is decoupled from the steeper increase of the correlation length of hexatic order and dynamic heterogeneity, while closely mirroring the decay length of two-body density correlations. Our results thus provide a clear example that other forms of order can play an important role in the slowing down of the dynamics, casting a serious doubt on the order-agnostic nature of the PTS length and its relevance to slow dynamics, provided that a polydisperse hard-disk system is a typical glass former.

INVESTIGATION OF THE CLUSTER SPIN-GLASS TRANSITION IN La2–xSrxCuO4 BY MEANS OF ANELASTIC SPECTROSCOPY

2000 ◽  
Vol 14 (25n27) ◽  
pp. 2785-2790
Author(s):  
A. PAOLONE ◽  
F. CORDERO ◽  
R. CANTELLI ◽  
M. FERRETTI
Keyword(s):  
Spin Glass ◽  
Acoustic Absorption ◽  
Magnetic Fluctuations ◽  
Relaxation Rates ◽  
Size Change ◽  
Slowing Down ◽  
Spin Glass Transition ◽  
Vibration Stress ◽  
Cluster Spin Glass ◽  
Measuring Frequency

A step-like increase of the acoustic absorption (Q-1) is found in La 2-x Sr x CuO 4 (x = 0.019, 0.025, 0.032 and 0.064) below the temperature (Tg) at which NQR and μSR measurements evidenced the formation of a cluster spin-glass (CSG) state. The sharp maxima appearing in the 139 La NQR and μSR relaxation rates indicate the slowing down of antiferromagnetic fluctuations below the measuring frequency (107-108 Hz in those experiments). The acoustic absorption does not appear to be due to the freezing of magnetic fluctuations, for which one expects a narrow peak; rather, it is attributed to the size change of the antiferromagnetically correlated clusters, produced through magnetoelastic coupling by the vibration stress.

scholarly journals Extraction of the Spin Glass Correlation Length

1999 ◽  
Vol 82 (2) ◽  
pp. 438-441 ◽  
Author(s):  
Y. G. Joh ◽  
R. Orbach ◽  
G. G. Wood ◽  
J. Hammann ◽  
E. Vincent
Keyword(s):  
Spin Glass ◽  
Correlation Length

scholarly journals Growth analysis of chub, Leuciscus cephalus (L.), and dace, Leuciscus leuciscus (L.), in the Úpoř stream using growth data of recaptured marked fish

2011 ◽  
Vol 50 (No. 7) ◽  
pp. 329-339 ◽  
Author(s):  
P. Vlach ◽  
J. Dušek ◽  
M. Švátora ◽  
P. Moravec
Keyword(s):  
Growth Rate ◽  
Age Groups ◽  
Growth Equation ◽  
Growth Data ◽  
Average Value ◽  
Slowing Down ◽  
Length Growth ◽  
Weight Relationship ◽  
Average Condition ◽  
The Mean

The length growth of chub and dace was observed. The scale method was used as well as data gained from recaptured individuals which were marked with visible elastomer tags and platinum wire tags with a coloured code placed under the first bony ray of the dorsal fin. The length-weight relationship for chub could be explained by the equation w = 0.00001.l <sup>3.067</sup> (r<sup>2</sup> = 0.96). The average condition coefficient reached 1.49. The growth was balanced, gradually slowing down. Von Bertallanffy growth equation had the form L<sub>t </sub>= 245.47(1 &ndash; e<sup>&ndash;0.206(t + 0.0333)</sup>). The average value of instantaneous monthly growth rate (G<sub>m</sub>) ranged between 0.4 and 4.3 (in %). Mean G<sub>m</sub> of particular age groups gradually decreased. G<sub>m</sub> varied seasonally, annually and in different parts of the stream. The length-weight relationship for dace was w = 0.000009.1<sup>3.0948 </sup>(r<sup>2</sup> = 0.97). The mean condition coefficient reached the value of 1.11. The length growth was balanced, gradually decreasing. Von Bertallanffy equation had the form L<sub>t</sub> = 216.28(1 &ndash; e<sup>&ndash;0.2536(t + 0.26094)</sup>). The instantaneous monthly growth rate ranged between &ndash;1.57 and 10.38 (in percentage). This indicator fluctuated according to the age, season and year. &nbsp;

SLOW DYNAMICS IN THE 'GRIFFITHS PHASE' OF THE 3D ± J ISING SPIN GLASS

1996 ◽  
Vol 07 (03) ◽  
pp. 371-378 ◽  
Author(s):  
TATSUO KOMORI ◽  
HAJIME TAKAYAMA
Keyword(s):  
Spin Glass ◽  
Relaxation Times ◽  
Relaxation Processes ◽  
Critical Dynamics ◽  
Griffiths Phase ◽  
Slow Dynamics ◽  
Ising Spin Glass ◽  
Slowing Down ◽  
Ising Spin ◽  
Crossover Behavior

Slow dynamics in the 'Griffiths phase' of the 3D ± J Ising spin glass is studied by means of Monte Carlo simulation, in which the spectra of (logarithms of) relaxation times, P (x) with x = ln τ, are analyzed in detail. At each temperature P (x) exhibits a characteristic crossover behavior at around a certain value xc which in turn tends to diverge toward the spin-glass critical temperature Tc. The contributions to the branch x ≲ xc are interpreted due to the ordinary critical slowing down process associated with Tc (critical dynamics). The behavior of P (x) at x ≲ xc, on the other hand, is consistent with the picture of relaxation processes of large, rare clusters which are related to the Griffiths singularity at the Curie temperature of the corresponding pure ferromagnet (cluster dynamics).

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