Lasing in dye vapor exposed to wide-band optical pumping

Abstract

We calculate numerically the exact relaxation spectrum of the totally asymmetric simple exclusion process (TASEP) with open boundary conditions on lattices up to 16 sites. In the low-and high-density phases and along the nonequilibrium first-order phase transition between these phases, but sufficiently far away from the second-order phase transition into the maximalcurrent phase, the low-lying spectrum (corresponding to the longest relaxation times) agrees well with the spectrum of a biased random walker confined to a finite lattice of the same size. The hopping rates of this random walk are given by the hopping rates of a shock (a domain wall separating stationary low-and high-density regions), which are calculated in the framework of a recently developed non-equilibrium version of Zel'dovich's theory of the kinetics of first-order transitions. We conclude that the description of the domain wall motion in the TASEP in terms of this theory of boundary-induced phase transitions is meaningful for very small systems of the order of ten lattice sites.

Dynamics of multichannel and quasi-homogeneous sliding discharge formation in rare gases

“…A quasi-homogeneous SGD in Ar, Xe of microsecond pulse duration was demonstrated in [3], where the initially formed separate leader channels quickly expanded during the pulse into a quasi-homogeneous plasma sheet. A research of transverse-discharge flashlamps of different size and energy [4][5][6][7][8][9][10][11], in which the discharge develops according to the SGD mechanism [11], showed good stability of emission brightness (15-20%) over the whole plasma sheet surface. This confirms and results from good uniformity of gap filling with the SGD plasma.…”

Transverse-discharge flashlamp operation: a surface model of gas breakdown as a first step towards representing discharge initiation

“…The term 'longitudinal discharge' applied to powerful flashlamps means that the current-flow direction coincides with a longitudinal lamp axis both for linear and for coaxial lamps. Transverse discharge flashlamps were elaborated and used for laser optical pumping, for example, in [2][3][4][5]. The maximum energy of tested lamps reaches 1 kJ at pulse durations of 200-250 ns.…”

“…The maximum energy of tested lamps reaches 1 kJ at pulse durations of 200-250 ns. In particular, precisely the high power and short pulse duration allowed us to induce the lasing action of a dye vapour with a high laser threshold [3] and to achieve a relatively low laser-beam divergence from a dye solution laser [5]. The relatively large width of a discharge slit (in the direction perpendicular to the current flow, i.e.…”

Lasing of Vapours of Complex Organic Compounds

“…The tunable radiation from lasers based on solutions of complex organic compounds was used for pumping the vapours. Laser action in vapours has been obtained with lamp pumping [39].…”

“…The homogeneity of the active medium substantially reduces the divergence of the beam in vapour lasers. Figure 9 shows the divergence of the laser beam as a function of pump density for lasers based on POPOP vapour and on POPOP dissolved in toluene, pumped with a nitrogen laser with an energy of 50mJ per pulse [39]. The divergence of the radiation of the solution laser for the two bases of the resonator is higher and increases with increasing pump power density, whereas it is constant for the vapour laser.…”