Terahertz lightwave control of non-equilibrium phases and collective modes in multi-band superconductors

2020 ◽  
Author(s):  
Martin Mootz ◽  
Ilias E. Perakis ◽  
Chirag Vaswani ◽  
Din H. Mudiyanselage ◽  
Xu Yang ◽  
...  
Keyword(s):  
Collective Modes ◽  
Equilibrium Phases ◽  
Non Equilibrium ◽  
Multi Band

Extractive distillation modeling of the ternary system 2-methoxy-2-methylpropane-methanol-butan-1-ol

2012 ◽  
Vol 66 (6) ◽  
Author(s):  
Zuzana Labovská ◽  
Pavol Steltenpohl ◽  
Elena Graczová
Keyword(s):  
Extractive Distillation ◽  
Model Complexity ◽  
Transfer Coefficients ◽  
Equilibrium Models ◽  
Nrtl Equation ◽  
Equilibrium Data ◽  
Real Behavior ◽  
Separation Equipment ◽  
Equilibrium Phases ◽  
Non Equilibrium

AbstractInfluence of model complexity on the separation equipment performance was investigated. As an example, separation of azeotrope formed by 2-methoxy-2-methylpropane and methanol was considered using butan-1-ol as an extractive solvent. Non-equilibrium model of a column for extractive distillation accounting for the mass and heat transfer rates was composed according to the rigorous Maxwell-Stefan theory. An empirical AICHE correlation was adopted for the calculation of binary mass transfer coefficients at column trays. Results of the column steady-state operation were compared with those obtained assuming different equilibrium models. Effect of the quality of the vapor-liquid equilibrium (VLE) description on the results of the separation simulation considering real behavior of either liquid or both equilibrium phases was tested. Real behavior of the liquid phase was computed according to the NRTL equation taking into account binary and, in some cases, also ternary equilibrium data. In case of real behavior of the vapor phase, the equation of state in the form of virial expansion was employed. Qualitative agreement was found comparing the simulation results calculated by equilibrium and non-equilibrium models of the extractive distillation column while using the same description of ternary VLE.

Non-Equilibrium Solidification in Cu-Mg-Sn Alloys for Tribological Applications

2010 ◽  
Vol 654-656 ◽  
pp. 1393-1396 ◽  
Author(s):  
Agustín Bravo ◽  
Rafael Schouwenaars ◽  
Víctor H. Jacobo ◽  
Armando Ortiz
Keyword(s):  
Rolled Strip ◽  
Metallic Elements ◽  
Laboratory Equipment ◽  
Iron And Steel ◽  
Equilibrium Solidification ◽  
Bearing Materials ◽  
Cold Rolled ◽  
Equilibrium Phases ◽  
Equilibrium Segregation ◽  
Non Equilibrium

Mg-containing bronzes have received little attention in general technological applications due to their relatively complex processing conditions. However, Mg is one of the few metallic elements which may exhibit good tribological compatibility with iron and steel and as such is a possible candidate to replace lead in sliding bearing materials. This work describes the casting of such alloys in the form of thin ingots to produce cold rolled strip, as is done for commercial Al-Sn-based ductile triboalloys. Sound ingots could be produced with simple laboratory equipment, yielding slabs in the compositional range of Cu1Mg1Sn, Cu1Mg5Sn, Cu5Mg1Sn and Cu5Mg5Sn. Cooling curves were monitored by embedded thermocouples. Invariant points could be identified after appropriate filtering of the signal but did not correspond to the ternary equilibrium. Segregation and non-equilibrium phases were confirmed by metallography.

A Modeling Study of Cyclical Phase Transformations

2005 ◽  
Vol 475-479 ◽  
pp. 3081-3086
Author(s):  
Jong K. Lee
Keyword(s):  
Phase Transitions ◽  
Mechanical Alloying ◽  
Phase Transformations ◽  
Molecular Dynamic ◽  
Dynamic Equilibrium ◽  
Equilibrium Phase ◽  
Two Dimensional ◽  
Lennard Jones ◽  
Equilibrium Phases ◽  
Non Equilibrium

Recent work has shown evidence of cyclical phase transformations taking place during mechanical alloying. Cyclical phase transformations resemble dynamic equilibrium in the sense that both equilibrium and non-equilibrium phases are simultaneously present during milling, but phase fractions vary during cyclical transformations. A brief thermodynamic and kinetic account is first discussed to establish the criteria for cyclical transformations. A two-dimensional molecular dynamic work is then presented to demonstrate cyclical phase transitions between an equilibrium and a non-equilibrium phase during mechanical alloying. A model binary crystal made of 57 Lennard-Jones atoms is studied to illustrate cyclical transitions between an equilibrium rhombus and a non-equilibrium square phase.

Synthesis of non-equilibrium phases in immiscible metals mechanically mixed by high pressure torsion

2011 ◽  
Vol 46 (12) ◽  
pp. 4296-4301 ◽  
Author(s):  
Tatsuya Miyazaki ◽  
Daisuke Terada ◽  
Yoji Miyajima ◽  
Challapalli Suryanarayana ◽  
Reiko Murao ◽  
...  
Keyword(s):  
High Pressure ◽  
High Pressure Torsion ◽  
Equilibrium Phases ◽  
Non Equilibrium

scholarly journals Evidence for metastable photo-induced superconductivity in K3C60

2021 ◽  
Author(s):  
M. Budden ◽  
T. Gebert ◽  
M. Buzzi ◽  
G. Jotzu ◽  
E. Wang ◽  
...  
Keyword(s):  
Optical Properties ◽  
High Temperature Superconductivity ◽  
Time Windows ◽  
Far Infrared ◽  
Theoretical Description ◽  
Organic Superconductors ◽  
Small Resistance ◽  
Equilibrium Phases ◽  
Short Time ◽  
Non Equilibrium

AbstractExcitation of high-Tc cuprates and certain organic superconductors with intense far-infrared optical pulses has been shown to create non-equilibrium states with optical properties that are consistent with transient high-temperature superconductivity. These non-equilibrium phases have been generated using femtosecond drives, and have been observed to disappear immediately after excitation, which is evidence of states that lack intrinsic rigidity. Here we make use of a new optical device to drive metallic K3C60 with mid-infrared pulses of tunable duration, ranging between one picosecond and one nanosecond. The same superconducting-like optical properties observed over short time windows for femtosecond excitation are shown here to become metastable under sustained optical driving, with lifetimes in excess of ten nanoseconds. Direct electrical probing, which becomes possible at these timescales, yields a vanishingly small resistance with the same relaxation time as that estimated by terahertz conductivity. We provide a theoretical description of the dynamics after excitation, and justify the observed slow relaxation by considering randomization of the order-parameter phase as the rate-limiting process that determines the decay of the light-induced superconductor.

scholarly journals Non-Equilibrium Phases and Magnetic Properties of Vapor-Quenched La-Fe Alloys

1989 ◽  
Vol 53 (1) ◽  
pp. 8-13 ◽  
Author(s):  
Koichi Takemura ◽  
Noriyuki Kataoka ◽  
Kenji Sumiyama ◽  
Yoji Nakamura
Keyword(s):  
Magnetic Properties ◽  
Fe Alloys ◽  
Equilibrium Phases ◽  
Non Equilibrium

Non-equilibrium phase formation

1990 ◽  
Vol 48 (4) ◽  
pp. 506-507
Author(s):  
Hiroshi Fujita
Keyword(s):  
Electron Irradiation ◽  
Equilibrium Phase ◽  
General Rule ◽  
High Energy ◽  
Atomic Scale ◽  
Irradiation Effect ◽  
In Situ Experiments ◽  
Equilibrium Phases ◽  
Non Equilibrium

The most important advantage of EM’s is in situ experiments on detailed processes of the same phenomena that occur in bulk materials. In recent years, in situ experiments with HVEM’s, in particular with a 3MV ultra-HVEM , has made it possible to create non-equilibrium phases, which do not exist in nature, or to control and design materials on an atomic scale. Namely, HVEM’s have developed to “Micro-Laboratory”, in which various material-treatments can be done, for natural science from powerful tools for characterization and/or identification of materials.l.The General Rule for Solid Amorphization The author and his cowerkers have succeeded in making amorphous solids of intermetallic compounds by high energy electron irradiation. Using the electron irradiation effect, necessary conditions for the formation of both non-equilibrium phases and extremly supersaturated solid structures[3,4] can be easily and precisely controlled.

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