1,022 research outputs found
On The Baxter's Q - Operator for the XXX Spin Chain
We discuss the construction of Baxter's Q-operator. The suggested approach
leads to the one-parametric family of Q-operators, satisfying to the
wronslian-type relations. Also we have found the generalization of Baxter
operators, with defines the nondiagonal part of the monodromy.Comment: 15 pages, LATEX fil
The Complex of Solutions of the Nested Bethe Ansatz. The A_2 Spin Chain
The full set of polynomial solutions of the nested Bethe Ansatz is
constructed for the case of A_2 rational spin chain. The structure and
properties of these associated solutions are more various then in the case of
usual XXX (A_1) spin chain but their role is similar
Ion characteristics of laser-produced plasma using a pair of collinear femtosecond laser pulses
Femtosecond laser-pulse absorption is studied in silicon ablation plasmas by means of a pair of identical 1016 W/cm21016W/cm2 collinear pulses separated on a picosecond time scale. The second laser-pulse modifies ionic characteristics of the preformed plasma, such as ion yield, ion energy, and average charge state. Resonance absorption is demonstrated to be the dominant mechanism by comparing results of ss and pp polarization. It is shown that maximum effects occur when a well defined critical density surface of the initial plasma forms together with an optimum density gradient scale length of kL = 1.5.kL=1.5. The optimal enhancement of ion yield, which occurs at 5 ps delay, is a factor of 2 greater than that produced by a single pulse with twice the energy of each individual double pulse. Applications are identified in regard to cluster beam formation and plasma isotope enrichment in ultrafast ablation plumes. © 2003 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70825/2/APPLAB-83-3-431-1.pd
The Friedrichs-Model with fermion-boson couplings II
In this work we present a formal solution of the extended version of the
Friedrichs Model. The Hamiltonian consists of discrete and continuum bosonic
states, which are coupled to fermions. The simultaneous treatment of the
couplings of the fermions with the discrete and continuous sectors of the
bosonic degrees of freedom leads to a system of coupled equations, whose
solutions are found by applying standard methods of representation of bound and
resonant states.Comment: 13 page
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