B. Dong

A nanoelectromechanical systems optical switch driven by optical gradient force

A nanoelectromechanical systems (NEMS) optical switch driven by optical gradient force is demonstrated. The switch consists of a free-standing ring resonator and two bus waveguides. When the free-standing ring is bended by the optical gradient force, the output transmission signal is tuned from the on-state to the off-state of the switch. The NEMS optical switch shows a switching time of 43.5 ns and a switching contrast of more than 25 dB. With its chip-scale integrability, the optical switch has potential applications in signal processing and high-speed optical communication networks.

A nanoelectromechanical systems actuator driven and controlled by Q-factor attenuation of ring resonator

In this Letter, an optical gradient force driven Nanoelectromechanical Systems (NEMS) actuator, which is controlled by the Q-factor attenuation of micro-ring resonator, is demonstrated. The actuator consists of a tunable actuation ring resonator, a sensing ring resonator, and a mechanical actuation arc. The actuation displacement can reach up to 14 nm with a measured resolution of 0.8 nm, when the Q-factor of the ring resonator is tuned from 15 × 103 to 6 × 103. The potential applications of the NEMS actuator include single molecule manipulation, nano-manipulation, and high sensitivity sensors.

A silicon-nanowire memory driven by optical gradient force induced bistability

In this paper, a bistable optical-driven silicon-nanowire memory is demonstrated, which employs ring resonator to generate optical gradient force over a doubly clamped silicon-nanowire. Two stable deformation positions of a doubly clamped silicon-nanowire represent two memory states (“0” and “1”) and can be set/reset by modulating the light intensity (<3 mW) based on the optical force induced bistability. The time response of the optical-driven memory is less than 250 ns. It has applications in the fields of all optical communication, quantum computing, and optomechanical circuits.

An on-chip opto-mechanical accelerometer

Optically enabled accelerometers offer superior displacement resolution and resilience to electromagnetic interference, which brought benefits to a wide range of applications ranging from inertial navigation to consumer electronics [1, 2]. However, impossible chip scale integration hampered their practical applications [2]. In this paper, a novel in-plane opto-mechanical accelerometer is demonstrated, which employs Whisper Gallery Mode (WGM) ring resonator (RR) as a displacement sensor that monolithically integrated with a nano-tethered proof mass with high mechanical Q-factor. Utilizing design optimized for strong opto-mechanical interactions allows the detection with high sensitivity of 3.279 pm/g at low-power operation.

Tunable meta-fluidic-materials base on multilayered microfluidic system

We demonstrate a multilayered microfluidic system with a flexible substrate, which has tunable optical chirality within THz spectrum range. The optical properties of the multilayered microfluidic system can be tuned by either changing the liquid pumped into each layer or stretching the flexible substrate. In experiment, the polarization rotation angle is tuned from zero (non-chiral structure) to 16.9° (strong-chiral structure). Furthermore, the tuning resolution can be well controlled due to the fine refractive index change of the liquid with different concentrations. It is feasible for the multilayered microfluidic structure to be integrated to an optofluidic system, where strong or tunable optical chirality are needed, which not only can be used as traditional optical components such as THz polarizers and filters but also has potential applications on imaging and sensor of bio-materials.

An all optical shock sensor based on buckled doubly-clamped silicon beam

In this paper, an all optical shock sensor based on a buckled doubly-clamped silicon beam is demonstrated. A buckled silicon beam is in the middle of two ring resonator and it has two stable positions. The silicon beam encounters a snap-through process upon a shock force, which can be monitored by measuring the resonance wavelength of the ring resonators. During experiment, a 0.15 nm wavelength is observed for a > 50 g shock. It has merits such as fast response, low power consumption and immunity to electromagnetic interference. It can be applied to inertial navigation system and automotive industry.

NEMS actuator driven by electrostatic and optical force with nano-scale resolution

We experimentally demonstrate a silicon nano-wire actuator with a nano-scale resolution and tunable actuation range. The nano-scale resolution is obtained through implementing different control regulations, including coarse tuning by the electrostatic force and precision tuning by the optical force. More specially, the optical force enabled silicon nano-wire actuator can break the classical NEMS 1/3 actuation range limit, extending the actuation range to an arbitrary limit in principle. This unique approach not only provides a simple, non-intrusive solution to the tunable air gap of NEMS devices, but also presents an ultra-sensitive optical read out of the mechanical motion.

NEMS integrated photonic system using nano-silicon-photonic circuits

This paper reports a NEMS integrated photonic system, which integrate tunable laser, optical cross correct and variable optical attenuators. The NEMS integrated photonic system is fabricated with nano-silicon-photonic fabrication technology to integrate various functions in a single silicon photonic circuit chip. The high light-confinement capability of the nano-silicon waveguides guarantees superior performance. The proposed NEMS integrated photonic system demonstrates large tuning range (45 nm), pure single-mode properties (45 dB side-mode-suppression ratio (SMSR)).

A nanomachined tunable oscillator controlled by electrostatic and optical force

We develop a miniaturized electrostatically tunable optomechanical oscillator, whose frequencies can be electrostatically tuned by as much as 10%. By taking advantage of the optical and the electrical spring, the oscillator achieves a high tuning sensitivity without resorting to mechanical tension. Particularly, the high-Q optical cavity greatly enhances the system sensitivity, making it extremely sensitive to the motional signal, which is often overwhelmed by background noise.

Nano-optomechanical static random access memory (SRAM)

This paper reports an on chip nano-optomechanical SRAM, which is integrated with light modulation system on a single silicon chip. In particular, a doubly-clamped silicon beam shows bistability due to the non-linear optical gradient force generated from a ring resonator. The memory states are assigned with two stable deformation positions, which can be switched by modulating the control lights power with the integrated optical modulator. The optical SRAM has write/read time around 120 ns, which is much faster as compared with traditional MEMS memory. Meanwhile, the write and read processes can happen concurrently without interference, which further reduces the time as compared with conventional electrical enabled SRAM.