Quadratic solitons with gain and loss

Propagation of soliton signals in quadratic nonlinear media under conditions for second-harmonic generation in the presence of multiple-frequency-band absorption and amplification is addressed. The reshaping and energy redistribution of the multiple-frequency solitons under the action of the single-band loss and gain is investigated and shown in detail. New chirped localized solitary-wave solutions that exactly compensate loss and gain are presented. Practical implementation conditions are discussed.