An apparatus includes a base having walls that define a track. The track has input and output ends and defines a coiled path that spirals inward from the input end, reaches an inflection point where a direction of curvature is reversed, and spirals outward towards the output end. The track is configured to receive and maintain a majority of an optical fiber in an at least substantially planar coiled arrangement. The apparatus also includes a first transition arm positioned at the input end and a second transition arm positioned at the output end. Each transition arm is configured to be mechanically coupled to the base and includes a groove configured to receive and maintain a portion of the optical fiber in an at least substantially straight orientation. The walls and transition arms are configured to maintain thermal contact with the optical fiber along its entire length.