The present invention demonstrates a technique for achieving milli-joule level and higher energy, broad bandwidth laser pulses centered around 2.4 micrometer with a kilohertz and other repetition rate. The key to such technique is to start with a broadband micro-joule level seed laser at around 2.4 micrometer, which could be generated through difference frequency generation, four-wave mixing process and other methods. This micro-joule level seed laser could then be amplified to above one milli-joule through chirped pulse amplification in a Cr2+:ZnSe or Cr2+:ZnS crystal pumped by a commercially available Ho:YAG or other appropriate suitable lasers. Due to the high seed energy, fewer gain passes are needed to achieve a milli-joule level output thus significantly simplifies laser architectures. Furthermore, gain narrowing effect in a typical chirped pulse amplifier is also mitigated and thus enable a broadband output.