Acoustic diamond resonators with ultrasmall mode volumes Article Swipe
YOU?
·
· 2020
· Open Access
·
· DOI: https://doi.org/10.1103/physrevresearch.2.033153
· OA: W3010149073
Quantum acoustodynamics (QAD) is a rapidly developing field of research,\noffering possibilities to realize and study macroscopic quantum-mechanical\nsystems in a new range of frequencies, and implement transducers and new types\nof memories for hybrid quantum devices. Here we propose a novel design for a\nversatile diamond QAD cavity operating at GHz frequencies, exhibiting effective\nmode volumes of about $10^{-4}\\lambda^3$. Our phononic crystal waveguide cavity\nimplements a non-resonant analogue of the optical lightning-rod effect to\nlocalize the energy of an acoustic mode into a deeply-subwavelength volume. We\ndemonstrate that this confinement can readily enhance the orbit-strain\ninteraction with embedded nitrogen-vacancy (NV) centres towards the\nhigh-cooperativity regime, and enable efficient resonant cooling of the\nacoustic vibrations towards the ground state using a single NV. This\narchitecture can be readily translated towards setup with multiple cavities in\none- or two-dimensional phononic crystals, and the underlying non-resonant\nlocalization mechanism will pave the way to further enhance optoacoustic\ncoupling in phoxonic crystal cavities.\n