My Current Research Activities
On this page I list a number of research activities in which I am currently active. Note that in most cases, I collaborate with colleagues, both at ASU, and in other locations, a few of whom are shown below. I have interests in quite a few topics, diverse in nature, and the listing here is merely the ones in which I have been active during the past year or so.
The Mesoscopic World
Mesoscopic systems (or devices) are midway between the very small and the large scales, typically from a few nanometers to a few hundred nanometers. On this scale, and at low temperatures, the quantum properties are readily discovered in measurements of the electronic transport through these structures. Indeed, the devices are very quantum objects.
John Bird, Buffalo
Yuchi Ochiai, Chiba
Nobuyuki Aoki, Chiba
Transport in Graphene
Graphene is a relatively new material which was isolated only a few years ago, and for which Andre Geim and Konstantin Novoselov recieved the Nobel prize. It is characterized by an very unusual band structure in which there is no gap and the bands are linear at the transition (see image at the right) from valence band to conduction band. This structure is known as Dirac-like bands, as they are characterized by a zero rest mass Dirac equation.
We study the electron transport through graphene by the use of an ensemble Monte Carlo technique, in which an ensemble of some 50,000 electrons is followed through the material. Each particle undergoes acceleration in the external electric field and scattering from a variety of sources. Intrinsic to the graphene are phonon scattering events due to the acoustic modes and the intervalley optical modes of the lattice. In addition, we use remote scattering generated by the polar phonons of the substrate material upon which the graphene is place. We also use impurities, usually remotely located, and defects that give short-range scattering potentials.
With Adre Geim in Mauterndorf, Austria in 2010.
Recent Publications in Graphene
D. K. Ferry, “Short range potential scattering and its role on graphene mobility,” Journal of Computational Electronics 12, 76 (2013) DOI 10.1007/s10825-012-0431-x
L. Huang, R. Yang, Y.-C. Lai, and D. K. Ferry, “Lead-position dependent regular oscillations and random fluctuations of conductance in graphene quantum dots,” Journal of Physics Condensed Matter 25, 085502 (2013) doi:10.1088/0953-8984/25/8/085502
B. Liu, R. Akis, and D. K. Ferry, “Conductance fluctuations in semiconductor nanostructures,” Journal of Physics Condensed Matter 25, 395802 (2013) doi:10.1088/0953-8984/25/39/395802
R. Somphonsane, H. Ramamoorthy, G. Bohra, G. He, D. K. Ferry, Y. Ochiai, N. Aoki, and J. P. Bird, “Fast energy relaxation of hot carriers near the Dirac point of graphene,” Nano Letters 13, 4305 (2013) DOI: 10.1021/nl4020777
M. V. Fischetti, J. Kim, S. Narayanan, Z.-Y. Ong, C. Sachs, D. K. Ferry, and S. J. Aboud, “Pseudo-potential based studies of electron transport in graphene and graphene nanoribbons,”, Journal of Physics Condensed Matter 25, 473202 (2013) doi:10.1088/0953-8984/25/47/473202
A. M. Mahjoub, A. Nicol, T. Abe, T. Ouchi, Y. Iso, M. Kida, N. Aoki, K. Miyamoto, T. Omatsu, J. P. Bird, D. K. Ferry, K. Ishibashi, and Y. Ochiai, “GR-FET application for high-frequency detection device,” Nanoscale Research Letters 8, 22-29 (2013) DOI: 10.1186/1556-276X-8-22
H. Ramamoorthy, R. Somphonsane, G. He, D. K. Ferry, Y. Ochiai, N. Aoki, and J. P. Bird, “Reversing hot-carrier energy-relaxation in graphene with a magnetic field,” Applied Physics Letters 104, 193115 (2014) DOI: 10.1063/1.4878535
B. Liu, R. Akis, and D. K. Ferry, “Conductance fluctuations in graphene nanoribbons,” Journal of Computational Electronics 13, 950-959 (2014) DOI: 10.1007/s10825-014-0613-9
B. Liu, R. Akis, and D. K. Ferry, “Conductance fluctuations in graphene subjected to short-range disorder,” Journal of Vacuum Science and Technology B 33, 04E101 (July/August, 2015) DOI: 10.1116/1.4917496
D. K. Ferry, R. Somphonsane, H. Ramamoorthy, and J. P. Bird, “Plasmon-mediated energy relaxation in grapheme,” Applied Physics Letters 107, 262103 (2015) DOI: 10.10631/1.4938760
D. K. Ferry, R. Somphonsane, H.Ramamoorthy, and J. P. Bird, “Energy relaxation of hot carriers in graphene via plasmon interactions,” Journal of Computational Electronics 15, 144-153 (2016) DOI 10.1007/s10825-015-0764-3
B. Liu, R. Akis, D. K. Ferry, G. Bohra, R. Somphonsane, H.Ramamoorthy, and J. P. Bird, “Conductance fluctuations in graphene in the presence of long range disorder,” Journal of Physics Condensed Matter 28, 135302 (2016) DOI: 10.1088/0953-8984/28/13/135302
The Heresy I have Spoken:
Perhaps a more fun area is that of challenging the accepted views of the world according to quantum mechanics. Over the years I have come to believe that Einstein and Schroedinger were correct in that the accepted view, according to Copenhagen, of quantum mechanics was incomplete. In some sense, this shows up clearly in some of the ideas for quantum computation. In any case, this had led me to write some heretical papers, a few of which are:
D. K. Ferry, “Quantum computing and probability,” Journal of Physics Condensed Matter 21, 474201 (2009) doi:10.1088/0953-8984/21/47/474201
D. K. Ferry, “Probing Bell’s inequality with classical systems,” Fluctuation and Noise Letters 9, 395 (2010) DOI: 10.1142/S0219477510000307
D. K. Ferry and L. B. Kish, “Noise and Bell’s theorem,” Fluctuation and Noise Letters 9, 423 (2010) DOI: 10.1142/S0219477510000320
D. K. Ferry, “Feynman on quantum simulation--Rush to judgement,” Journal of Computational and Theoretical Nanoscience 8, 953 (2011) DOI:10.1166/jctn.2011.1775
D. K. Ferry, “Are there quantum jumps,” International Journal of Modern Physics: Conference Series 33, 1460358 (2014) DOI: 10.1142/S2010194514603585
D. K. Ferry, The Copenhagen Conspiracy, in preparation, to be published by Pan Stanford Publishing, Singapore