公开(公告)号：WO1990004866A1

公开(公告)日：1990-05-03

申请号：PCT/US1989000690

申请日：1989-02-24

Applicant: LEITNER, GREENE & CHRISTENSEN

Inventor： LEITNER, GREENE & CHRISTENSEN ,  STOICHEFF, Boris, P. ,  EFTHIMIOPOULOS, Thomas

IPC: H01S03/09

CPC classification number: H01S3/0979 ,  H01S3/225

Abstract: A method and apparatus for generating an inverted population in a gas are provided. Gas is excited at one pressure, so as to give a portion of the gas the energy of a higher electronic state. The gas is then expanded to a lower pressure, so as to concentrate that portion of the gas into a reduced number of energy levels in the higher electronic state. This concentrated population should then produce an inverted population relative to a lower electronic state. Inverted populations can then be used for stimulating emission, in a variety of laser devices, or in an amplifier. A lower curve (1) represents the ground state of energy and a middle curve (3) represents the first excited electronic state energy; an upper curve (5) represents the upper electronic energy states. To generate a population inversion unexcited atoms in the flat portion (13) are excited into flat portion (15) or the upper flat portions (17).