1 research outputs found
Micromechanical high-Q trampoline resonators from strained crystalline InGaP for integrated free-space optomechanics
Tensile-strained materials have been used to fabricate nano- and
micromechanical resonators with ultra-low mechanical dissipation in the kHz to
MHz frequency range. These mechanical resonators are of particular interest for
force sensing applications and quantum optomechanics at room temperature.
Tensile-strained crystalline materials that are compatible with epitaxial
growth of heterostructures would thereby allow realizing monolithic free-space
optomechanical devices, which benefit from stability, ultra-small mode volumes
and scalability. In our work, we demonstrate micromechanical resonators made
from tensile-strained InGaP, which is a crystalline material that can be
epitaxially grown on III-V heterostructures. The strain of the InGaP layer is
defined via its Ga content when grown on (Al,Ga)As. In our case we realize
devices with a stress of up to 470\,MPa along the crystal
direction. We characterize the mechanical properties of the suspended InGaP
devices, such as anisotropic stress, anisotropic yield strength, and intrinsic
quality factor. We find that the latter degrades over time. We reach mechanical
quality factors surpassing at room temperature with a -product
as high as with trampoline-shaped micromechanical resonators,
which exploit strain engineering to dilute mechanical dissipation. The large
area of the suspended trampoline resonator allows us to pattern a photonic
crystal to engineer its out-of-plane reflectivity in the telecom band, which is
desired for efficient signal transduction of mechanical motion to light.
Stabilization of the intrinsic quality factor together with a further reduction
of mechanical dissipation through hierarchical clamping or machine
learning-based optimization methods paves the way for integrated free-space
quantum optomechanics at room temperature in a crystalline material platform.Comment: fixed typos, added more material on crystal anisotropy and on
fabrication; 15 pages incl. appendix, 13 figure