Yuerui (Larry) Lu received his Ph.D. degree from Cornell University, the school of Electrical and Computer Engineering, in 2012. He holds a B.S. degree from department of Applied Physics at University of Science and Technology of China. In 2013, he joined the Australian National University as a research fellow and lecturer under the Future Engineering Research Leadership Fellowship. He is now a full professor at the ANU. His research interests include MEMS/NEMS sensors and actuators, nano-manufacturing technologies, renewable energy harvesting, biomedical novel devices, low-dimensional quantum materials, opto-electronic devices, etc. He was the recipient of several awards, including the competitive Young Innovator Award from Springer Publishing Group in 2020, Future Leader Fellowship and Paul Korner Innovation Award from National Heart Foundation of Australia in 2019, Outstanding Supervisor Award for 3MT (3 minutes thesis) Competition from Australian National University in 2018, ACT Young Tall Poppy of 2016, Media and Outreach Award from Australian National University in 2015, Discovery Early Career Research Award (DECRA) from Australian Research Council (ARC) in 2014, Future Engineering Research Leadership Fellow from Australian National University in 2013, MRS Graduate Student Award (Silver) in 2012 from Materials Research Society, Best Poster Award in 2012 from Cornell NanoScale Facility Annual Meeting, Daisy Yen Wu Scholarship in 2012 from Cornell University, Chinese Government Award for outstanding Ph.D. students in 2010, Guo Moruo Presidential Award in 2003 from University of Science and Technology of China, etc. He is serving as a reviewer for several journals, including Nature Communications, Light: Science and Applications, Advanced Materials, ACS Nano, Small, Applied Physics Letters, Nanotechnology, Optics Express, Optics Letters, Sensors and Actuators A: Physical, etc. He is serving as an associate editor for the nature publishing group journal Scientific Reports. 

My research focuses on nanotechnologies, including micro/nano-electro-mechanical sensors and actuators, nano-scale energy conversion devices, biomedical devices, novel low-dimensional quantum materials and their integration, etc. I am looking for highly motivated Ph.D. graduate students who are majoring in applied physics, electrical engineering, mechanical engineering, chemistry, materials science engineering, biomedical engineering, or other closely related areas to join my research team. We always look for dedicated undergraduate or master students to join us, to do creative work in rapidly growing field and generate co-authored publications.

1. MEMS/NEMS based novel biomedical devices

The ability to detect bio-molecule at ultra-low concentrations (e.g. atto-molar) will enable the possibility of detecting diseases earlier than ever before. A critical challenge for any new bio-sensing technology is to optimize two metrics --- shorter analysis time, and higher concentration sensitivity in clinically relevant small volumes. Moreover, practical considerations are equally important: simplicity of use, mass producible (low cost), and ease of integration within the clinical structure. Compared with other methods, nano-electro-mechanical system (NEMS) based bio-sensors are promising in clinical diagnostics because of their extremely high mass sensitivity, fast response time and the capability of integration on chip. We have demonstrated a low concentration DNA (atto-molar sensitivity) optically interrogated ultrasonic mechanical mass sensor, which has ordered nanowire (NW) array on top of a bilayer membrane. This method represents a mass-based platform technology that can sense molecules at low concentrations, which could be useful for early-stage disease detection. We can develop this sensor further to measure an array of biomarkers (e.g. DNA or proteins), by providing both the needed specificity and sensitivity in physiological disease (e.g. cancer) detection.

Recommended references:

• B. Ilic et al., Enumeration of DNA molecules bound to a nanomechanical oscillator. Nano Letters 5, 925-929 (2005).
• T. P. Burg et al., Weighing of biomolecules, single cells and single nanoparticles in fluid. Nature 446, 1066-1069 (2007).
• H. G. Craighead, Nanoelectromechanical systems. Science 290, 1532-1535 (2000).
• A. K. Naik, M. S. Hanay, W. K. Hiebert, X. L. Feng, M. L. Roukes, Towards single-molecule nanomechanical mass spectrometry. Nature Nanotechnology 4, 445-450 (2009).
• Y. Lu, S. Peng, D. Luo, A. Lal, Low-concentration mechanical biosensor based on a photonic crystal nanowire array. Nature Communications 2, 578 (2011).

2. Atomically thin opto-electronic devices (LED, solar cells) and/or mechanical devices based on novel two dimensional nano-materials

Two-dimensional (2D) nano-materials, such as molybdenum disulfide (MoS2) and graphene, have atomic or molecular thickness, exhibiting promising applications in nano-electro-mechanical systems. Graphene is a one-atom thick carbon sheet, with atoms arranged in a regular hexagonal pattern. Molybdenum disulfide (MoS2) belongs to transition metal dichalcogenides (TMD) semiconductor family YX2 (Y=Mo, W; X=S, Se, Te), with a layered structure. This project aims to demonstrate novel opto-electronic devices, like light-emitting diode (LED), solar cells, etc. These 2D nano-materials can also be integrated into nano-electro-mechanical systems, enabling ultra-sensitive mechanical mass sensors, with single molecule or even single atom sensitivities. Moreover, the mechanical resonators based on these 2D nano-materials would be a perfect platform to investigate quantum mechanics, opto-mechanics, material internal friction force, nonlinear physics, etc.

Recommended references:

• J. S. Bunch et al., Electromechanical resonators from graphene sheets. Science 315, 490-493 (2007).
• R. A. Barton et al., Photothermal self-oscillation and laser cooling of graphene optomechanical systems. Nano Letters 12, 4681-4686 (2012).
• Radisavljevicb, Radenovica, Brivioj, Giacomettiv, Kisa, Single-layer MoS₂ transistors. Nature Nanotechnology 6, 147-150 (2011).
• M. Osada, T. Sasaki, Two-dimensional dielectric nanosheets: Novel nanoelectronics from nanocrystal building blocks. Advanced Materials 24, 210-228 (2012).

3. Optical nonlinearities in 2D crystals

Entangled photons have many applications — from fundamental tests of quantum mechanics, to practical implementations in quantum key distribution, quantum imaging and ultraprecise metrology. Generating entangled photons with broad spectral and angular widths is a long-standing goal in quantum optics. A platform on which to achieve this goal is highly nonlinear atomically thin 2D crystals: due to their scale and optical properties, these two-dimensional crystalline layers can be designed into fully operational, miniaturised quantum photonic chips.

Since the discovery of graphene in 2004, many materials with a stable monolayer form have been found, including the important subclass of transition-metal dichalcogenides (MX2; M = Mo/W; X = S/Se/Te). These materials are centrosymmetric when in bulk form, but the inversion symmetry is broken when thinning them down to monolayer thickness. As a result, 2D monolayers feature an atomic-level dipole that gives them extraordinary physical properties including dichroism, ferroelectricity, and piezoelectricity. In particular, the monolayers exhibit enormous second-order susceptibility χ(2) that enables efficient nonlinear optical processes.

Highly nonlinear 2D materials can in principle be used for spontaneous parametric down-conversion (SPDC). SPDC is a well developed tool in quantum optics to produce entangled photons. So far, this process has exclusively been observed at the macroscopic scale on periodically poled bulk crystals. This project aims to investigate enhancement techniques to bring SPDC to the atomic scale and use nonlinear 2D crystals as integrated highly entangled photon sources.

4. Quantum emitters in 2D materials

Single photon sources are critical for future quantum technologies such as quantum computing, quantum simulators, and unconditionally secure quantum communication.

The recent discovery of quantum emitters in two-dimensional (2D) materials offers a very promising source of single photon sources, with compelling applications for the next generation of integrated photonic devices. In contrast to their 3D counterparts, quantum emitters in amotically thin 2D lattices are not surrounded by any high refractive index medium. This eliminates total internal and Fresnel reflection of emitted single-photons, allowing intrinsically near-ideal extraction efficiency.

Quantum emission has been reported from a diversity of materials, in semiconducting transition metal dichalcogenides (TMDs) and insulating hexagonal boron nitride (hBN). The large band gap of the latter even allows one to resolve the zero phonon line (ZPL) at room temperature and thwarts non-radiative recombination of the localized exciton. Thus, single-photon emitters in hBN have an intrinsically high quantum efficiency which leads to significantly brighter emission. These single-photon sources are suitable for many practical field applications due to their resistance to ionizing radiation, temperature stability over a range spanning 800 K, long-term operation and capabilities for integration with photonic networks, as well as easy handling.

[1] ACS Photonics 6, 1955 (2019)

[2] Nanoscale 11, 14362 (2019)

[3] Nat. Commun. 10, 1202 (2019)

[4] ACS Photonics 5, 2305 (2018)

[5] J. Phys. D 50, 295101 (2017)

6. Power generation for wearable devices

Wearable devices are shaping this digital world. It will endow the world's highest intelligent creatures -humans with new attributes such as digitization, Internet of Things (IoT), quantitative sensing and detection. Green and sustainable energy supply for flexible wearable devices is a challenging and crucial research frontier. This project will focus on the cutting-edge power generation approaches, behind which physics of various energy conversion mechanisms. Based on application scenarios in healthcare, industrial inspection, structural monitoring, armed forces and consumer electronics, etc., a system architecture of the wearable flexible system is to be designed and tested. It is expected to make breakthroughs and reshape the digital world by developing all-in-one printable wearable electronics, self-powered self-aware wearable system, hybrid-integrated system on chip for flexible electronics, and IoT-enabled self-contained system towards full life cycle monitoring.