相关论文: Stability of ferroelectric ice

Ordinary ice has a proton-disordered phase which is kinetically metastable, unable to reach, spontaneously, the ferroelectric (FE) ground state at low temperature where a residual Pauling entropy persists. Upon light doping with KOH at low…

Spin ice is a frustrated magnetic system that at low temperatures exhibits a Coulomb phase, a classical spin liquid with topological order and deconfined excitations. This work establishes the presence of a Coulomb phase with coexisting…

The recent discovery of Spin-ice is a spectacular example of non-coplanar spin arrangements that can arise in the pyrochlore A2B2O7 structure. We present magnetic and thermodynamic studies on the metallic-ferromagnet pyrochlore Sm2Mo2O7.…

A new phase of ice, named ice XV, has been identified and its structure determined by neutron diffraction. Ice XV is the hydrogen-ordered counterpart of ice VI and is thermodynamically stable at temperatures below ~130 K in the 0.8 to 1.5…

We unravel the dynamical stability of a fully polarized one-dimensional ultracold few-fermion spin-1/2 gas subjected to inhomogeneous driving of the itinerant spins. Despite the unstable character of the total spin-polarization the…

Among the many ice polymorphs, ice I, that is present in nature at ambient pressure, occurs with two different structures, i.e. the stable hexagonal (Ih) or the metastable cubic (Ic) one. An accurate analysis of cubic ice Ic was missing…

Weck et al. (1) report on the existence and stability fields of two superionic (SI) phases of H2O ice at high P-T (P-T) conditions, which has been a topic of static and dynamic experiments and theoretical calculations (see Ref. (2) and…

The phase diagram of ice is studied by a quasi-harmonic approximation. The free energy of all experimentally known ice phases has been calculated with the flexible q-TIP4P/F model of water. The only exception is the high pressure ice X, in…

Recent experiments on the spin-ice material Dy2Ti2O7 suggest that the Pauling "ice entropy", characteristic of its classical Coulombic spin-liquid state, may be lost at low temperatures [D. Pomaranski et al., Nature Phys. 9, 353 (2013)].…

The intrinsic noncollinear spin patterns in rare-earth pyrochlore are physically interesting, hosting many emergent properties, e.g. spin ice and monopole-type excitation. Recently, the magnetic monopole excitation of spin ice systems was…

Properties of the $\omega$ structure are investigated for 27 transition elements from the viewpoints of thermodynamical and mechanical stability based on first-principles calculations. The thermodynamical stability of the $\omega$ structure…

Physical properties of a pyrohafnate compound Pr2Hf2O7 have been investigated by ac magnetic susceptibility \chi_ ac(T), dc magnetic susceptibility \chi(T), isothermal magnetization M(H) and heat capacity C_p(T) measurements on…

Pyrochlore materials are characterized by their hallmark network of corner-sharing rare-earth tetrahedra, which can produce a wide array of complex magnetic ground states. Ferromagnetic Ising pyrochlores often obey the "two-in-two-out" spin…

We discuss the problem of proton motion in Hydrogen bond materials with special focus on ice. We show that phenomenological models proposed in the past for the study of ice can be recast in terms of microscopic models in close relationship…

A new model of localized highly frustrated ferromagnetism is presented: kagome spin ice. By use of analytical and Monte Carlo calculations its massive groundstate entropy is evaluated. Monte Carlo calculations are also used to explore the…

Chromium based inverse Heusler compounds of the type Cr2YZ (Y=Co, Fe; Z=Al, Ga, In, Si, Ge, Sn) have been proposed as fully compensated half-metallic ferrimagnets. Such materials are of large interest for spintronics because they combine…

We have found that the geometrically frustrated spin chain compound Ca3Co2O6 belonging to Ising like universality class with uniaxial anisotropy shows kinetic arrest of first order intermediate phase (IP) to ferrimagnetic (FIM) transition.…

Water exhibits rich polymorphism, where more than 20 crystalline phases have been experimentally reported. Five of them are metastable and form at low temperatures by either heating amorphous ice or degassing clathrate hydrates. However,…

The properties of some forms of water ice reserve still intriguing surprises. Besides the several stable or metastable phases of pure ice, solid mixtures of water with gases are precursors of other ices, since in some cases they may be…

From high precision measurements of the complex dielectric constant of H2O ice, we identify the critical temperatures of the phase transition into and out of ice XI from ice Ih to occur at T_Ih-IX=58.9 K and T_IX-Ih=73.4 K. For D2O,…