Glassy thermal anomalies due to dipolar reorientations? Specific heat of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">N</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>-Ar-CO alloys

Nicholls, Christopher; Ya-don, LI; Haase, David G.; Conradi, Mark S.

doi:10.1103/physrevlett.59.1317

Cited by 32 publications

(12 citation statements)

References 20 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Reconciliation of our results with the experiment in Ref. [19,20] stems from the fact that pairs of N 2 molecules do produce symmetric TLSs in the ArN 2 system [23]. Calculation -KBr:CN is perhaps the most studied disordered lattice showing universal characteristics.…”

supporting

confidence: 80%

“…[12], that CN flips comprise the relevant low energy TLSs [21,22]. However, for long, advance in this direction was hindered because of experiments showing that the substitution of the symmetric N 2 molecules for the asymmetric CO molecules in N 2 /Ar/CO does not change its universal characteristics [19,20]. Our results here, in conjunction with the theory in Ref.…”

supporting

confidence: 58%

“…Note, that although we focus here on the simplest single impurity excitations, our analysis does not exclude the possibility of symmetric and asymmetric multi-impurity excitations [16][17][18]. Such excitations are expected to be significant especially for systems where single impurity excitations do not produce symmetric TLSs [19,20].…”

mentioning

confidence: 99%

See 2 more Smart Citations

Identification of Strong and Weak Interacting Two-Level Systems in KBr:CN

Gaita‐Ariño¹,

Schechter²

2011

Phys. Rev. Lett.

View full text Add to dashboard Cite

Tunneling two-level systems (TLSs) are believed to be the source of phenomena such as the universal low temperature properties in disordered and amorphous solids, and 1/f noise. The existence of these phenomena in a large variety of dissimilar physical systems testifies for the universal nature of the TLSs, which however, is not yet known. Following a recent suggestion that attributes the low temperature TLSs to inversion pairs [M. Schechter and P. C. E. Stamp, arXiv:0910.1283.] we calculate explicitly the TLS-phonon coupling of inversion symmetric and asymmetric TLSs in a given disordered crystal. Our work (a) estimates parameters that support the theory in M. Schechter and P. C. E. Stamp, arXiv:0910.1283, in its general form, and (b) positively identifies, for the first time, the relevant TLSs in a given system.

show abstract

supporting

confidence: 80%

supporting

confidence: 58%

See 1 more Smart Citation

Identification of Strong and Weak Interacting Two-Level Systems in KBr:CN

Gaita‐Ariño¹,

Schechter²

2011

Phys. Rev. Lett.

View full text Add to dashboard Cite

show abstract

“…In short, the anomalous heat capacity at temperature T is believed due to the small fraction of CN-that: (a) have energy minima within kT of each other, and (b) have minima separated by a small enough energy barrier that tunneling can occur within experimental time scales (10, 1 1). It was remarked (9) that this theory should also describe the physics of CO/N2/Ar, another orientational glass with some asymmetric rotors. Because an energy difference of order kT between the two orientations of a molecule is required to generate a heat capacity at temperature T , the low temperature excess heat capacity would be expected to be due only to T flips of CO and not to T flips of symmetric N2 molecules.…”

Section: Introductionmentioning

confidence: 99%

“…The CO asymmetry was a key aspect of a recent test (9) of a theory of glassy two-level systems (10,11). It was proposed that the two-level systems 'On leave of absence from College of William and Mary.…”

Section: Introductionmentioning

confidence: 99%

CO/N₂/Ar orientational glass: magnetic resonance

Walton¹,

Wu²,

Conradi³

1988

Can. J. Chem.

Self Cite

View full text Add to dashboard Cite

. J. Chem. 66, 680 (1988).The nrnr lineshapes and linewidths of KCN/KBr, N2/Ar, and CO/N2/Ar are compared at corresponding states and are found to agree closely. This indicates a similar kind of orientational freezing, despite major differences in the anisotropic molecular interactions. The line narrowing and T2 data are explicable by two different theories. The one involves an orientation probability function, while the other invokes a broad homogeneous distribution of correlation times. Spin-lattice relaxation measurements indicate that T I and dielectric loss are controlled at low temperatures by nearly n flips of CO molecules. On a compare les formes et les largeurs des raies de rmn du KCN/KBr, du N2/Ar et du CO/N2/Ar dans des Ctats correspondants et on a trouvt qu'ils sont trks semblables. Ce resultat indique que, malgre des differences majeures dans les interactions molCculaires anisotropes, leurs orientations lors de leurs congelations sont semblables. Les donnies relatives au retricissement des bandes et aux valeurs de T2 peuvent Ctre expliquees par deux thCories differentes. La premiere implique une fonction de probabilite dand l'orientation alors que l'autre fait appel B une distribution homogene large des temps de correlation. Des mesures de relaxation spin-rkseau indiquent que la valeur de T I ainsi que la perte dielectrique sont contr6lCes, B basse temperature, par pratiquement n inversions des molecules de CO.[Traduit par la revue]

show abstract

How Universal Are the Glassy States in Solids with a Structural Instability?

Roth

Hegenbarth

1990

Physica Status Solidi (b)

View full text Add to dashboard Cite

Amorphous solids, like glasses or polymers, show unusual thermal, dielectric, and elastic properties at low temperatures T 6 1 K / I / . This so-called glassy behaviour is caused by low-energetical localized states (LS) 1 2 , 3 / . However, a noticeable glassy behaviour was also found at low temperatures iq crystalline substances, for example ferroelectrics , / 4 , 5 1 . In high-temperature superconductors glassy properties were detected, too /6, 7 / .The common origin f o r the generation of LS in such different materials is not yet explained in detail. The following effects can be important in forming a glassy state: (i) the glass transition, e.g. in glasses and polymers /8/, (ii) random field effects caused by impurities or other defects / 9 / , (iii) frustration effects due to anisotropic interactions / l o , 11/, and (iv) structural phase transitions (SPT) /12/, e.g. in ferroelectrics /13/.In this short note it is shown that materials withan SPT at thetemperature T C display a strongly marked glassy behaviour if Tc is nearly equal to the Debye temperature eD.For that purpose, in Fig. la

show abstract

Glassy thermal anomalies due to dipolar reorientations? Specific heat ofN2-Ar-CO alloys

Cited by 32 publications

References 20 publications

Identification of Strong and Weak Interacting Two-Level Systems in KBr:CN

Identification of Strong and Weak Interacting Two-Level Systems in KBr:CN

CO/N₂/Ar orientational glass: magnetic resonance

How Universal Are the Glassy States in Solids with a Structural Instability?

Contact Info

Product

Resources

About

Glassy thermal anomalies due to dipolar reorientations? Specific heat ofN2-Ar-CO alloys

Cited by 32 publications

References 20 publications

Identification of Strong and Weak Interacting Two-Level Systems in KBr:CN

Identification of Strong and Weak Interacting Two-Level Systems in KBr:CN

CO/N2/Ar orientational glass: magnetic resonance

How Universal Are the Glassy States in Solids with a Structural Instability?

Contact Info

Product

Resources

About

CO/N₂/Ar orientational glass: magnetic resonance