Baun will report to the Laval Rocket; Martinsen has been assigned to the Rockford IceHogs.
Baun, 25, has played 117 games in the AHL with Rockford, tallying 15 goals and 28 assists for 43 points. The third-year pro has also played five career games in the NHL, all with Chicago.
Martinsen, 27, skated in 64 NHL games between Montreal and Colorado last season, and has compiled seven goals and 11 assists for 18 points in 119 career NHL contests.
Martinsen spent 10 games in the AHL with San Antonio in 2015-16, notching one goal and one assist.