The interplay between electron correlation and nuclear quantum effects makes our understanding of elemental hydrogen a formidable challenge. Here, we present the phase diagram deuterium at low temperatures high-pressure ($P > 300$ GPa by accounting for highly accurate electronic enthalpies. We evaluated internal energies diffusion Monte Carlo, while motion anharmonicity have been included stoch...

The thermal expansion of the heavy fermion compound CeRh2Si2 has been measured under pressure as a function of temperature using strain gages. A large anomaly associated to the Néel temperature has been detected even above the suspected critical pressure Pc ∼ 1.05 GPa where no indication of antiferromagnetism has been observed in calorimetry experiments sensitive to the entropy change. An unexp...

the time evaluation of quantum entropy in a four-level double- type atomic system is theoretically investigated. quantum entanglement of the atom and its spontaneous emission fields is then discussed via quantum entropy. it is found that the degree of entanglement can be increased by the quantum interference induced by spontaneous emission. the phase dependence of the atom-field entanglement is...

The condensation of magnetic quasiparticles into the nonmagnetic ground state has been used to explain novel magnetic ordering phenomena observed in quantum spin systems. We present neutron scattering results across the pressure-induced quantum phase transition and for the novel ordered phase of the magnetic insulator TlCuCl3, which are consistent with the theoretically predicted two degenerate...

A quantum spin liquid is a state of matter characterized by quantum entanglement and the absence of any broken symmetry. In condensed matter, the frustrated rare-earth pyrochlore magnets Ho2Ti2O7 and Dy2Ti2O7, so-called spin ices, exhibit a classical spin liquid state with fractionalized thermal excitations (magnetic monopoles). Evidence for a quantum spin ice, in which the magnetic monopoles b...

The electronic conductance at zero temperature through a quantum wire with side-connected asymmetric quantum ring (as a scatter system) is theoretically studied using the non-interacting Hamiltonian Anderson tunneling method. In this paper we concentrate on the configuration of the quantum dot rings. We show that the asymmetric structure of QD-scatter system strongly influences the amplitude an...