Nonequilibrium pulsed femtosecond semiconductor disk laser

A surface-emitting semiconductor laser system configured to operate in a mode-locked regime, the laser system comprising:

• an optical resonator having an optical axis;
• a semiconductor laser chip within the optical resonator, the semiconductor laser chip containing a semiconductor gain medium,
• wherein said semiconductor gain medium is characterized by a gain spectrum, the gains spectrum having a bandwidth that includes a first wavelength,
• wherein said semiconductor gain medium has a first multiple quantum well (MQW) unit, said first MQW unit defined by a sequence of at least three first quantum wells (QWs) that are spaced substantially non-equidistantly with respect to one another;
• and
• a pump source in operable communication with said semiconductor laser chip and configured to pump energy to the semiconductor gain medium to produce excited-state carriers in the first MQW unit,
• wherein said semiconductor laser system is configured to form a standing optical wave within said semiconductor laser chip at a frequency of the first wavelength, said standing optical wave having first and second immediately neighboring modes located along the optical axis within the semiconductor gain medium, said first and second nodes formed on the opposite sides of said first MQW unit.