Abstract: A heat sink assembly may include an alignment body with an opening configured to receive a crystal rod, wherein the opening is configured to maintain a crystalline orientation of the crystal rod relative to a physical orientation of the alignment body. The heat sink assembly may include a first cooling stack, wherein the first cooling stack includes a first cutout to receive the crystal rod and the alignment body. The heat sink assembly may include a second cooling stack, wherein the second cooling stack includes a second cutout to receive the crystal rod and the alignment body, and wherein the first cooling stack and the second cooling stack are configured to mate and at least partially sandwich the crystal rod and the alignment body.