Ordering of Helium Mixtures in Porous Gold

Tulimieri, Daryl; Yoon, Jongsoo; Chan, Moses H. W.

doi:10.1103/physrevlett.82.121

Cited by 56 publications

(69 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…9). Measurements by Tuliemeri et al 27 have also shown that aerogel density affects the shape of isotherms far from the critical point -they become sharper and flatter in high porosity aerogels.…”

Section: Discussionmentioning

confidence: 98%

Helium adsorption in silica aerogel near the liquid-vapor critical point

2005

View full text Add to dashboard Cite

We have investigated the adsorption and desorption of helium near its liquid-vapor critical point in silica aerogels with porosities between 95% and 98%. We used a capacitive measurement technique which allowed us to probe the helium density inside the aerogel directly, even though the samples were surrounded by bulk helium. The aerogel's very low thermal conductivity resulted in long equilibration times so we monitored the pressure and the helium density, both inside the aerogel and in the surrounding bulk, and waited at each point until all had stabilized. Our measurements were made at temperatures far from the critical point, where a well defined liquid-vapor interface exists, and at temperatures up to the bulk critical point. Hysteresis between adsorption and desorption isotherms persisted to temperatures close to the liquid-vapor critical point and there was no sign of an equilibrium liquid-vapor transition once the hysteresis disappeared. Many features of our isotherms can be described in terms of capillary condensation, although this picture becomes less applicable as the liquid-vapor critical point is approached and it is unclear how it can be applied to aerogels, whose tenuous structure includes a wide range of length scales.

show abstract

Section: Discussionmentioning

confidence: 98%

Helium adsorption in silica aerogel near the liquid-vapor critical point

2005

View full text Add to dashboard Cite

show abstract

“…1) The specific surface area of the materials is in the order of a few m 2 /g. [20] Pattern formation during dealloying seems to be a consequence of local surface passivation by clustering of Au adatoms in combination with continuous etching of Ag. [17] Within this simple model, the length scale of the structure should be a function of the diffusion length of clustering vacancies and Au adatoms which are continuously generated during dealloying.…”

Section: Dealloyingmentioning

confidence: 99%

Nanoporous Plasmonic Metamaterials

et al. 2008

View full text Add to dashboard Cite

We review different routes for the generation of nanoporous metallic foams and films exhibiting well-defined pore size and short-range order. Dealloying and templating allows the generation of both two-and threedimensional structures which promise a well defined plasmonic response determined by material constituents and porosity. Viewed in the context of metamaterials, the ease of fabrication of samples covering macroscopic dimensions is highly promising, and suggests more in-depth investigations of the plasmonic and photonic properties of this material system for photonic applications.

show abstract

“…Exact analytical calculations have also been performed in one dimension [3] and generalized to a Bethe lattice [4]: in this case, the transition only exists for z ≥ 4, where z is the connectivity of the lattice. Such a transition has been observed in thin Co/CoO films [5] and Cu-Al-Mn alloys [6], and we have recently suggested [7] that it may also be associated to the change in the adsorption behavior of 4 He in dilute silica aerogels [8]. In all these systems, activated processses are too slow to allow thermal equilibration on experimental time scales, which makes the T = 0 RFIM a relevant model for understanding the out-of-equilibrium behavior.…”

Section: Introductionmentioning

confidence: 99%

Metastable states and T=0 hysteresis in the random-field Ising model on random graphs

2005

View full text Add to dashboard Cite

We study the ferromagnetic random-field Ising model on random graphs of fixed connectivity z (Bethe lattice) in the presence of an external magnetic field H. We compute the number of singlespin-flip stable configurations with a given magnetization m and study the connection between the distribution of these metastable states in the H − m plane (focusing on the region where the number is exponentially large) and the shape of the saturation hysteresis loop obtained by cycling the field between −∞ and +∞ at T = 0. The annealed complexity ΣA(m, H) is calculated for z = 2, 3, 4 and the quenched complexity ΣQ(m, H) for z = 2. We prove explicitly for z = 2 that the contour ΣQ(m, H) = 0 coincides with the saturation loop. On the other hand, we show that ΣA(m, H) is irrelevant for describing, even qualitatively, the observable hysteresis properties of the system.

show abstract

Ordering of Helium Mixtures in Porous Gold

Cited by 56 publications

References 21 publications

Helium adsorption in silica aerogel near the liquid-vapor critical point

Helium adsorption in silica aerogel near the liquid-vapor critical point

Nanoporous Plasmonic Metamaterials

Metastable states and T=0 hysteresis in the random-field Ising model on random graphs

Contact Info

Product

Resources

About