Generation of isolated attosecond pulses with large electric area in a dense resonant medium

Abstract

Obtaining unipolar half-cycle optical pulses of femto- and attosecond duration with a large electrical area is an urgent but difficult task. The reason for the emerging difficulties lies in the existence of the rule of conservation of the electrical area of the pulse, which does not allow converting a bipolar pulse into a unipolar one. In this work, it is shown that in a resonant medium a few-cycle pulse can be converted into two unipolar pulses separated in time by a distance that is an order of magnitude or more longer than the duration of the initial pulse. This allows in a number of problems to consider such pulses separately as unipolar. The estimation of the electric area value relative to its "atomic scale" is carried out. Keywords: attosecond pulses, unipolar pulses, subcycle pulses, electrical area of pulses.

Half-cycle and unipolar pulses (Topical Review)

“…Possible ways of half-cycle attosecond pulse formation, when a single-cycle pulse propagates in a two-level medium in the regime of self-induced transparency (SIT) were considered in [34]. In this case, two half waves of a single-cycle pulse behave as separate SIT solitons.…”

“…The problem of unipolar pulse generation and their applications are described in reviews [7][8][9][10][11]. Here we focus on recent advances of unipolar and quasi-unipolar extremely short pulse production [23][24][25][26][27][28][29][30][31][32][33][34][35][36], consider recent experiments that show unipolarity of pulsed radiation [37,38], discuss some problems of unipolar pulse actions on wave packets [15][16][17][18][19][20] and so on.…”

Generation of unipolar pulses of terahertz radiation with a large electric area

“…In this paper estimates of the electric area of pulses are also given. The paper [17] theoretically shows the possibility of obtaining half-cycle isolated subfemtosecond pulses with large electric area due to the phenomenon of self-induced transparency.…”