Hexagonal boron nitride cavity optomechanics

Abstract

Hexagonal boron nitride (hBN) is an emerging layered material that plays a key role in a variety of twodimensional devices, and has potential applications in nanophotonics and nanomechanics. Here, we demonstrate the first cavity optomechanical system incorporating hBN. Nanomechanical resonators consisting of hBN beams with predicted thickness between 8 nm and 51 nm were fabricated using electron beam induced etching and positioned in the optical nearfield of silicon microdisk cavities. A 160 fm/ √ Hz sensitivity to the hBN nanobeam motion is demonstrated, allowing observation of thermally driven mechanical resonances with frequencies between 1 and 23 MHz, and mechanical quality factors reaching 1100 at room temperature in high vacuum. In addition, the role of air damping is studied via pressure dependent measurements. Our results constitute an important step towards realizing integrated optomechanical circuits employing hBN. arXiv:1809.04023v2 [physics.optics]

Initialization and read-out of intrinsic spin defects in a van der Waals crystal at room temperature

“…This stimulates further research in hBN-based heterostructures for quantum sensing applications and drives interest into deterministically engineering single centres. The work will also accelerate the research into the spin-optomechanics with hBN, particularly given the established theoretical framework 31 and advances in nanofabrication of resonators 32 . Further, with an increased control over isotopic purity, coherent manipulation of spin states may become feasible, yielding potentially high coherence times-as predicted theoretically 33 .…”

Stability of the discrete time-crystalline order in spin-optomechanical and open cavity QED systems

“…Besides, a stronger γ leads to a higher critical spin-cavity coupling λ c such that stronger spin-cavity coupling λ is needed, which imposes a challenge to its experimental realization. For cavity loss rate γ = 0.05ω T as considered in Figures 4c and 5c, the quality factor Q is about 20, which provides a balance between spin cooling and loss to make experimental realization more feasible [52]. Overall, negligible spin dephasing, weak spin damping and appropriate cavity loss are suggested in realizing transient DTC order in such an optomechanical system.…”

“…As a type of van der Waals materials, hBN can be integrated with plasmonic, nanophotonic, and potentially more complex structures [46][47][48][49][50]. The hBN membranes have low mass, small out-of-plane stiffness, high elasticity modulus and strong tensile strength, which make them a promising candidate for high-Q mechanical resonators and highsensitivity sensors [51,52]. A spin-mechanical system based on color centers in a suspended hBN mechanical resonator has been proposed [53,54], which can even simulate the Rabi model in the ultrastrong coupling regime.…”

Hexagonal boron nitride: a review of the emerging material platform for single-photon sources and the spin–photon interface

“…Another interesting application is cavity optomechanics recently demonstrated using h-BN [168]. Here nanomechanical resonators consisting of h-BN beams were positioned on high mechanical Q silicon microdisk cavities.…”