A continuously tunable vertical actuator with subnanometer resolution is presented. It consists of a heterostructure cantilever which has collapsed over a 125 nm thick nanogap. Its operating principle relies on the temperature dependence of the adhesion energy between two InGaAs surface quantum wells. Deflections from -17 to 5 nm with a precision better than three atomic layers have been measured.
Bibliographical noteFunding Information:
The authors would like to thank Chris Palmstrøm and Sukgeun Choi of the University of Minnesota and Jin Dong Song of the Korean Institute of Science and Technology for MBE growth. This work was sponsored by the National Science Foundation under Grant No. ECS-0631241.