Abstract. We consider the problem of non degenerate in energy metastable states forming a series in the framework of reversible finite state space Markov chains. We assume that starting from the state at higher energy the system necessarily visits the second one before reaching the stable state. In this framework we give a sharp estimate of the exit time from the metastable state at higher ener...

%e detect the radiatively driven electric quadrupole transition to the metastable Dsy2 state in a single, laser-cooled Hg D ion by monitoring the abrupt cessation of the fluorescence signal from the laser-excited 'Si/2 Pi~2 first resonance line. %hen the ion "jumps" back from the metastable D state to the ground S state, the S P resonance fluorescence signal immediately returns. The statistical...

Metastability of a particle trapped in a well with a time-periodically oscillating barrier is studied in the Floquet formalism. It is shown that the oscillating barrier causes the system to decay faster in general. However, avoided crossings of metastable states can occur with the less stable states crossing over to the more stable ones. If in the static well there exists a bound state, then it...

We study the process of thermal activation mediated by sphaleron transitions by analyzing the real-time dynamics of the decay out of equilibrium in a 1+1 dimensional field theory with a metastable state. The situation considered is that of a rapid supercooling in which the system is trapped in a metastable state at a temperature larger than the mass of the quanta, but smaller than the energy to...

A metastable liquid may exist under supercooling, sustaining the liquid below the melting point such as supercooled water and silicon. It may also exist as a transient state in solid-solid transitions, as demonstrated in recent studies of colloidal particles and glass-forming metallic systems. One important question is whether a crystalline solid may directly melt into a sustainable metastable ...

We present a combined experimental and theoretical study on the radiative lifetime of CO in the aΠ1,2, v = 0 state. CO molecules in a beam are prepared in selected rotational levels of this metastable state, Stark-decelerated and electrostatically trapped. From the phosphorescence decay in the trap, the radiative lifetime is measured to be 2.63 ± 0.03 ms for the aΠ1, v = 0, J = 1 level. From sp...

We present a combined experimental and theoretical study on the radiative lifetime of CO in the aΠ1,2, v = 0 state. CO molecules in a beam are prepared in selected rotational levels of this metastable state, Stark-decelerated and electrostatically trapped. From the phosphorescence decay in the trap, the radiative lifetime is measured to be 2.63 ± 0.03 ms for the aΠ1, v = 0, J = 1 level. From sp...

We prepare and study a metastable attractive Mott-insulator state formed with bosonic atoms in a three-dimensional optical lattice. Starting from a Mott insulator with Cs atoms at weak repulsive interactions, we use a magnetic Feshbach resonance to tune the interactions to large attractive values and produce a metastable state pinned by attractive interactions with a lifetime on the order of 10...

A photo-crystallographic study of Fe(btr)2(NCS)2.H2O was performed in order to describe the modification of structures and charge densities on going from the ground low spin (LS) state to the metastable high spin (HS) state during the LIESST phenomenon at 15K. Related photo-magnetic and spectroscopic measurements are also described. We show that at 15K, the thermally quenched and photo-induced ...