The Nanoelectronics Group
We are currently looking for candidates for our Ph.D. project "Seeing is believing: Microscopy-capable nanoelectronics for simultaneous optical and electrical study of biomolecules", more details here.
We have several research interests within the broader topic of the physics of nanoscale electronic devices and condensed matter physics. Our current focus is in three main areas:
1. Biological-microscopy-capable nanoelectronic devices: Advanced biosensors featuring nanoscale electronic devices have been the subject of intense research interest for many years. For the most part, such devices have been developed on traditional Si/SiO2 substrates for use as purely electronic sensors without any capacity for simultaneous optical microscopy. In parallel, biological microscopy has made major leaps forward both in resolution and the simplicity and reduced cost of the infrastrucure, for example, 3D printed high-resolution microscopes using cellphone cameras are a thriving development frontier. Biological microscopy methods use ultrathin glass, a highly unconventional substrate for nanoscale electronic devices. This 'substrate mismatch' has led to nanoscale electronic biosensors and advanced biological microscopy evolving in isolation despite an interest in similar biological targets and questions. We are currently working on nanoscale electronic devices designed such that biological microscopy can be performed at the device simultaneously with the electrical measurements. This work involves collaborations with University of Tokyo in Japan, Lund University in Sweden, Swansea University in Wales, Victoria University of Wellington in New Zealand, TU Dresden in Germany and other groups at UNSW.
2. Novel Materials for Electronics: Conduction in electronics is all about electrons but in biological systems it's all about ions because free electrons don't remain free long enough in those systems. An important challenge in bioelectronics is thus the transduction of electronic signals into ionic signals and vice versa. Nanomaterials, e.g., semiconductor nanowires or carbon nanotubes, can have an interesting role here. Their high surface-to-volume ratio means electronic conduction is readily influenced by their external ionic environment. This can be mediated by ion-conductive polymer materials to enable devices with solid-solid ion-to-electron transduction interfaces. We began in this direction by making the first nanowire transistors with multiple independently controllable ion-gel gate structures, first with poly(ethylene oxide), and more recently using the ionomer Nafion. We are presently exploring other ion-active materials both for coupling with traditional semiconductors and independent use. This work involves collaborations with Swansea University in Wales, Lund University in Sweden, the University of Copenhagen in Denmark and other groups at UNSW.
3. Beyond semiconductor nanowire devices: Semiconductor nanowires have been a focus of major efforts internationally for many years. All the way through this nanowires were nanowires, high-aspect ratio rod-like structures with nanoscale diameter and microscale length, with their growth on a crystalline substrate templated either by a metal nanoparticle or a hole in an amorphous oxide mask. We have recently been working on an interesting variant of the oxide mask approach where a rectangular slot in the mask is used to grow a 2D nanofin. These structures are essentially a nanowire that is 'stretched' in one direction in the sense that the growth mechanics, crystal structure and faceting is the same as a nanowire but the resulting object is 2D rather than 1D. These nanofins can be transferred to sit flat on a separate substrate, and then used as 'nanoscale Hall bars' for the creation of device structures that aren't possible with nanowires due to their limited dimensionality. This work involves collaborations with the Australian National University and Delft University of Technology in the Netherlands.
These projects are funded by the Australian Research Council Discovery Projects Scheme through Grants DP170102552 "Building up quantum electronics with tailored semiconductor nanostructures" (Adam Micolich & Philippe Caroff) and DP170104024 "Bioelectronic logic" (Paul Meredith & Adam Micolich), as well as the University of New South Wales through internal grant schemes. We have also benefitted from a JSPS International Fellowship on microscopy-capable nanowire transistors and on-going collaboration with the University of Tokyo, as well as an on-going collaboration with the EU Horizon 2020 Project Bio4Comp on parallel network-based biocomputation.
Key Recent Publications -- For complete list see 'Publications' tab in menu to left
- "Nanopore blockade sensors for ultrasensitive detection of proteins in complex biological samples", K. Chuah, Y. Wu, S.R.C. Vivekchand, K. Gaus, P.J. Reece, A.P. Micolich and J.J. Gooding, Nature Communications 10, 2109 (2019).
- "Regaining a spatial dimension: Mechanically transferrable two-dimensional InAs nanofins grown by selective area epitaxy", J. Seidl, J.G. Gluschke, X. Yuan, S. Naureen, N. Shahid, H.H. Tan, C. Jagadish, A.P. Micolich and P. Caroff, Nano Letters 19, 4666 (2019).
This paper was subject of a news article in Materials Today (29/7/19).
- "p-GaAs nanowire metal-semiconductor field-effect transistors with near-thermal limit gating", A.R. Ullah, F. Meyer, J.G. Gluschke, S. Naureen, P. Caroff, P. Krogstrup, J. Nygard and A.P. Micolich, Nano Letters 18, 5673 (2018).
- "Using ultrathin parylene films as an organic gate insulator in nanowire field-effect transistors", J.G. Gluschke, J. Seidl, R.W. Lyttleton, D.J. Carrad, J.W. Cochrane, S. Lehmann, L. Samuelson and A.P. Micolich, Nano Letters 18, 4431 (2018).
This paper was subject of a news article on Materials Today (23/7/18).
- "Near-thermal limit gating in heavily doped III-V semiconductor nanowires using polymer electrolytes", A.R. Ullah, D.J. Carrad, P. Krogstrup, J. Nygard and A.P. Micolich, Physical Review Materials 2, 025601 (2018).
- "Hybrid nanowire ion-to-electron transducers for integrated bioelectronic circuitry", D.J. Carrad, A.B. Mostert, A.R. Ullah, A.M. Burke, H.J. Joyce, H.H. Tan, C. Jagadish, P. Krogstrup, J. Nygard, P. Meredith and A.P. Micolich, Nano Letters 17, 827 (2017).
- "A conducting polymer with enhanced electronic stability applied in cardiac models", D. Mawad, C. Mansfield, A. Lauto, F. Perbellini, G.W. Nelson, J. Tonkin, S.O. Bello, D.J. Carrad, A.P. Micolich, M.M. Mahat, J. Furman, D. Payne, A.R. Lyon, J.J. Gooding, S.E. Harding, C.M. Terracciano and M.M. Stevens, Science Advances 2, e1601007 (2016).
- "InAs nanowire transistors with multiple, independent wrap-gate segments", A.M. Burke, D.J. Carrad, J.G. Gluschke, K. Storm, S. Fahlvik Svensson, H. Linke, L. Samuelson and A.P. Micolich, Nano Letters 15, 2836 (2015).
This paper was subject of a news article on Nanotechweb.org (27/4/15). - "Using polymer electrolyte gates to set-and-freeze threshold voltage and local potential in nanowire-based devices and thermoelectrics", S. Fahlvik Svensson, A.M. Burke, D.J. Carrad, M. Leijnse, H. Linke, and A.P. Micolich, Advanced Functional Materials 25, 255 (2015).
- "Electron-beam patterning of polymer electrolyte films to make multiple nanoscale gates for nanowire transistors", D.J. Carrad, A.M. Burke, R.W. Lyttleton, H.J. Joyce, H.H. Tan, C. Jagadish, K. Storm, H. Linke, L. Samuelson and A.P. Micolich, Nano Letters 14, 94 (2014).
This paper was subject of a news article in Materials Today (17/2/14).
- "Quantum Point Contacts: Double or Nothing?", A.P. Micolich, Nature Physics 9, 530 (2013).
This was an invited News & Views article to discuss two recent Nature articles on the 0.7 anomaly in QPCs by Bauer et al. and Iqbal et al. -
"The effect of (NH4)2Sx passivation on the (311)A GaAs surface and its use in AlGaAs/GaAs heterostructure devices", D.J. Carrad, A.M. Burke, P.J. Reece, R.W. Lyttleton, D.E.J. Waddington, A. Rai, D. Reuter, A.D. Wieck and A.P. Micolich, Journal of Physics: Condensed Matter 25, 325304 (2013).
This paper was the cover article for Issue 32 of Volume 25 of Journal of Physics: Condensed Matter.
- "Extreme Sensitivity of the Spin-Splitting and 0.7 Anomaly to Confining Potential in One-Dimensional Nanoelectronic Devices", A.M. Burke, O. Klochan, I. Farrer, D.A. Ritchie, A.R. Hamilton and A.P. Micolich, Nano Letters 12, 4495 (2012).
- "Impact of Small-angle Scattering on Ballistic Transport in Quantum Dots", A.M. See, I. Pilgrim, B.C. Scannell, R.D. Montgomery, O. Klochan, A.M. Burke, M. Aagesen, P.E. Lindelof, I. Farrer, D.A. Ritchie, R.P. Taylor, A.R. Hamilton and A.P. Micolich, Physical Review Letters 108, 196807 (2012).
This paper was highlighted by news articles in Science Daily, PhysOrg and Science Alert, and a podcast for Materials Today. - "What lurks below the last plateau: experimental studies of the 0.7 x 2e2/h conductance anomaly in one-dimensional systems", A.P. Micolich, J. Phys.: Condens. Matter 23, 443201 (2011).
This paper is a 73 page review article on the 15 year history of the 0.7 plateau in quantum point contacts.
"Realizing lateral wrap-gated nanowire FETs: Controlling gate length with chemistry rather than lithography", K. Storm, G. Nylund, L. Samuelson and A.P. Micolich, Nano Letters 12, 1 (2012).
This paper is the cover article for the Jan. 2012 edition of Nano Letters.
This paper was highlighted by news articles in Materials Today, PhysOrg and Zeitnews.