1. Department of Physics, University of California, Santa Barbara, California 93106, USA

Correspondence to: Dustin Kleckner¹ Correspondence and requests for materials should be addressed to D.K. (Email: dkleckner@physics.ucsb.edu).

Micromechanical resonators, when cooled down to near their ground state, can be used to explore quantum effects such as superposition and entanglement at a macroscopic scale^{1, 2, 3}. Previously, it has been proposed to use electronic feedback to cool a high frequency (10 MHz) resonator to near its ground state⁴. In other work, a low frequency resonator was cooled from room temperature to 18 K by passive optical feedback⁵. Additionally, active optical feedback of atomic force microscope cantilevers has been used to modify their response characteristics⁶, and cooling to approximately 2 K has been measured⁷. Here we demonstrate active optical feedback cooling to 135  15 mK of a micromechanical resonator integrated with a high-quality optical resonator. Additionally, we show that the scheme should be applicable at cryogenic base temperatures, allowing cooling to near the ground state that is required for quantum experiments—near 100 nK for a kHz oscillator.

MORE ARTICLES LIKE THIS

These links to content published by NPG are automatically generated.