PODMEMS: Enables MEMS to change performance on demand (POD).
What is transformational?: A PODMEMS device is one that is able to monitor its state and feed back forces onto its proof mass that are proportional to displacement, velocity, or acceleration. Such feedback effectively increases or decreases the system's effective stiffness, damping, or mass. Effective quantities may be positive, zero, or negative. How is it different from existing technologies?: Existing MEMS have a constant mass, damping, and stiffness, which are subject to process variations, so no two MEMS behave identically. Existing MEMS are limited by manufacturing constraints. Incremental advances of existing MEMS are made by pushing the limits of manufacturing, which reduces yield and robustness. PODMEMS can change such quantities on demand. What is the potential impact?: PODMEMS are able to correct for process variations, behave identically, drastically change resonance frequencies, change damping to over-damped or under-damped, lock into a frequency that is independent of temperature, match primary to secondary modes in a gyro, increase effective quality factor, increase nonlinearity, mimic the behavior of another device, behave as a smaller or larger sized device, etc. PODMEMS enable behaviors that are far beyond the limits of existing manufacturing methods.
Planar microphone array for spatial audio recording
Capture and reproduction of 3D audio is becoming increasingly important for many applications including AR/VR, media, human-machine communications, smart homes, hearing aids, teleconferencing and active noise control in confined spaces. Current microphone arrays used to capture 3D sound are binaural, tetrahedral or spherical in shape, making them bulky and difficult to integrate into miniaturized devices. ANU researchers have addressed this limitation by developing a planar 2D microphone array technology that allows 3D spatial sound to be recorded by a compact microphone array arranged in a planar geometry. This system exploits a special property of the Legendre functions (which represents the sound field) and uses a combination of omni-directional microphone units to achieve the full functionality of a spherical microphone array in a very compact, planar form factor. Custom developed algorithms associated with the planar array produce spatial audio signal streams in the form of ‘Higher Order Ambisonics” which is compatible with the latest industrial standard for spatial sound encoding (MPEG-H) as well as the spatial sound format commonly used for YouTube VR contents. Thus, the planar array is compatible with most spatial sound rendering engines on the market and its compact size makes it incorporable into various consumer electronics.
Control of electromagnetic wave scattering via a Huygens’ metadevice
Our time-varying metadevice is made of both electric and magnetic meta-atoms with independently controlled modulation, and the phase of this modulation is imprinted on the scattered parametric waves (sidebands), controlling their shapes and directions. Using optimized modulation signals, we achieve a high conversion efficiency of over 75% from the carrier wave to the target sidebands and the sideband scatterings are fully controlled by the amplitude and phase of modulation. Manipulation of these sidebands is of great importance from both a fundamental and application point-of-view. A number of optical systems with dynamic modulation rely on sideband control, e.g. sideband cooling and magnet-free optical isolation. Time-modulated linear arrays (TMAs) also rely on the ability to generate multiple beams at different sidebands, with different shapes and features, for use in multi-function radars, direction finding and in mobile wireless communication. Our metadevice can be applied to a wide-range of devices and applications, and as such, it could benefit a variety of company types and may present multiple potential licensing opportunities. We are interested in identifying industry partners that have a need for this technology, in order to create functional prototype devices. This technology is patent protected.
Quantum Dot Laser Portfolio
This technology includes a way to epitaxially grow quantum dot lasers on Si that are free of misfit dislocation. These misfit dislocation free quantum dot lasers offer an extended lifetime and improve device performance reliability while maintaining high performance levels. It also offers a process of using a less expensive alternative for growing light emitting material and a low-cost, highly scalable approach to integrating a compound-semiconductor laser or light source with silicon-photonic circuitry that provides an enabling technology for the low-cost manufacture of efficient lasers on silicon. Last, the portfolio includes a technology that proposes a photonic integrated circuit based on quantum dots, grown on Si that allows lasers, modulators, and photodetectors to be integrated.
MicroLEDs with Ultralow Leakage Current
As the ratio of the sidewall perimeter to emitting area of an LED increases, the effects of sidewall damage and surface recombination are more pronounced. Therefore, microLEDs with light-emitting areas less than 100x100 µm2, are especially susceptible to parasitic leakage. Normally, sidewall passivation using conformal dielectric deposition is employed to reduce leakage current. However, sidewall passivation using merely dielectric deposition is insufficient to remove the effects of sidewall damage and surface recombination in microLEDs. This technology describes a sidewall passivation method by chemical treatment on microLEDs that minimizes the effects of sidewall damage and surface recombination. The passivated microLEDs can achieve higher efficiency, and at smaller device sizes, than devices without sidewall treatments.