Cryogenic piezoelectric actuators

In this paper, PMN-PT single crystal piezoelectric stack actuators and flextensional actuators were designed, prototyped and characterized for space optics applications. Single crystal stack actuators with footprint of 10 mm x 10 mm and the height of 50 mm were assembled using 10 mm x 10 mm x 0.15 mm PMN-PT plates. These actuators showed stroke of 65 - 85 μm at 150 V at room temperature, and > 30 μm stroke at 77 K. Flextensional actuators with dimension of 10 mm x 5 mm x 7.6 mm showed stroke of > 50 μm at room temperature at driving voltage of 150 V. A flextensional stack actuator with dimension of 10 mm x 5 mm x 47 mm showed stroke of ~ 285 μm at 150 V at room temperature, and > 100 μm at 77K under driving of 150 V should be expected. The large cryogenic stroke and high precision of these actuators are promising for cryogenic optics applications.