Detail Project and Funding

Abstract: Abstract: ABNANOTECH targets the realization and study of applied and fundamental aspects of a novel class of atomic-scale devices for applications in the field of electronics, spintronics, plasmonics, and quantum simulation of complex Hamiltonians. The devices we have in mind are based on the manipulation of electrons, cold atoms, and single “impurities” (such as single atoms, molecules, and ions) in two-dimensional (2D) natural or artificial crystals. The former class includes graphene, silicene, germanene and other one-atom thick materials such as 2D transition-metal dichalcogenides and 2D electron gases at the interface between correlated oxides; similar functionalities are offered by the 2D surface states of thin-film chalcogenide topological insulators. The latter class includes instead man-made lattices created by nanopatterning the surface of an ordinary semiconductor hosting a 2D electron gas (solid-state artificial lattices) or by interference of laser beams with suitable spatial arragements (flexible optical lattices). ABNANOTECH is a highly-interdisciplinary project involving personnel of the Italian National Research Council who are very activive internationally and displaying varying degrees of competence. Our consortium is composed by experts in the growth of advanced materials, the characterization of bulk crystals and nanostructured devices with various spectroscopic tools – including angle-resolved photoemission spectroscopy (ARPES), Raman inelastic light scattering (ILS), scanning tunneling microscopy (STM), transmission electron microscopy (TEM), electron energy loss spectroscopy (EELS), ultrasonic force microscopy (UFM), and scanning ion conductance microscopy (SICM) – and the manipulation of electrons, atoms, and molecules in solid-state or optical lattices. Last but not least, ABNANOTECH relies on a pool of theoretical condensed matter physicists who are capable of carrying out model Hamiltonian and/or ab initio calculations. The theoretical members of the consortium will support all the applied and experimental activities but also make predictions for the observation of novel fundamental behaviors at the nanoscale.

The scenario outlined above requires a blend of different expertise ranging from the manipulation of cold atoms and electrons in artificial lattices to the control over single dopant atoms in solid-state environments or the realization and study of 2D crystals such as graphene and transition-metal dichalcogenides. The drive towards the implementation of such an highly integrated research project originates from the belief that the large overlap of underlying quantum-mechanical concepts that are at the foundations of so many research fields (graphene, cold atoms, and nanoscale semiconductor physics) at the cutting edge of low-energy physics will be pivotal for the development of disruptive atomic-scale quantum technologies.

Objectives: ABNANOTECH focuses on three main objectives, which we are going to list below.

Objective 1: Graphene and other 2D atomic crystals, 2D electron gases (EGs) at oxide interfaces, and thin-film topological insulators for electronic, optoelectronic, plasmonic, and spintronic devices. Bulk materials such as graphite or transition-metal dichalcogenides (TMDs) can be exfoliated to create 2D crystals [1]. The most studied example is graphene, a 2D system of Carbon atoms tightly packed in a honeycomb lattice. Other 2D systems [2], which are currently being intensively investigated, include silicene and germanene [3,4], 2D TMDs [5] such as MoS2, 2DEGs at the interface of correlated oxides (such as LaAlO3/SrTiO3) [6], and 2D surface states of chalcogenide topological insulators (e.g. Bi/Se and/or Bi/Te alloys) [7,8]. Gate-tunable 2D materials pave the way for research activities of both fundamental interest (linked e.g. to the possibility of studying electronic properties of systems with peculiar band structures [9]) and technological relevance. In the latter respect, we foresee potentially disruptive applications in several fields including, for example, sensing (e.g. ultrasensitive MEMS and NEMS, ultrafast and compact photodetectors, etc), nanoelectronics (e.g. ultrathin RF transistors), and optoelectronics (e.g. smart windows, cheap solar cells, etc).
BIBLIOGRAPHY
[1] K.S. Novoselov et al., Proc. Natl. Acad. Sci. U.S.A. 102, 10451 (2005).
[2] F. Bonaccorso et al., Mater. Today 15, 564 (2012).
[3] S. Cahangirov et al., Phys. Rev. Lett. 102, 236804 (2009).
[4] P. Vogt et al., Phys. Rev. Lett. 108, 155501 (2012).
[5] Q.H. Wang et al., Nature Nanotech. 7, 699 (2012).
[6] For a recent review see e.g. H.Y. Hwang et al., Nature Mater. 11, 103 (2012).
[7] M.Z. Hasan and C. L. Kane, Rev. Mod. Phys. 82, 3045 (2010).
[8] X.-L. Qi and S.-C. Zhang, Rev. Mod. Phys. 83, 1057 (2011).
[9] M.I. Katsnelson, Graphene: Carbon in Two Dimensions (Cambridge University Press, Cambridge, 2012).

Objective 2: Artificial solid-state and optical lattices for new functionalities and quantum simulation of complex matter.
Novel routes for the realization of artificial lattices with control over the single constituent units such as atoms, molecules, electrons, photons, and ions offer the possibility to understand complex phenomena of condensed matter and high-energy physics in ultra-simplified toy-model systems [1,2]. These systems allow the simulation of exotic Hamiltonians, thereby offering the possibility to unravel complex behaviors of many-particle systems that are very poorly understood. Examples of hard problems we want to tackle with our quantum simulators include 2D Hubbard [3] and massless Dirac fermion physics [4,5], lattice spin physics and quantum magnetism [6,7], quantum spin Hall phases [8,9], and the emergence of Wigner crystals and molecules in low-dimensional systems [10].
BIBLIOGRAPHY
[1] I. Buluta and F. Nori, Science 326, 108 (2009).
[2] M. Lewenstein, A. Sanpera, and V. Ahufinger, Ultracold atoms in optical lattices: simulating many-body quantum systems (Oxford University Press, Oxford, 2012).
[3] T. Esslinger, Annu. Rev. Condens. Matter Phys. 1, 129 (2010).
[4] L. Tarruell et al., Nature 483, 302 (2012).
[5] A. Singha et al., Science 332, 1176 (2011).
[6] J. Struck et al., Science 333, 996 (2011).
[7] D. Greif et al., arXiv:1212.2634 (2012).
[8] Y. Zhang and C. Zhang, Phys. Rev. B 84, 085123 (2011).
[9] P. Ghaemi, S. Gopalakrishnan, and T.L Hughes, Phys. Rev. B 86, 201406(R) (2012).
[10] See e.g. J.J. Wang et al., Phys. Rev. B 86, 075110 (2012) and references therein.

Objective 3: Solid-state technologies based on single-atom/molecule control.
Future technological revolutions capable of overcoming the limits dictated by Moore’s law require the development of methods for the creation, manipulation, and control of isolated atoms, which are incidentally also exquisite quantum systems. The capabilities of embedding isolated atoms in macroscopic solid-state devices, or to nanomanipulate single molecules become enabling technologies for single-spin devices in the area of quantum information, single-dopant transistors, and solitary-dopant optoelectronics [1, 2]. In the realm of photonics and plasmonics, single-emitter excitations allow for ultra-sensitive devices, sub-shot-noise imaging, and novel architectures for (quantum) ICTs [3]. ABNANOTECH ultimately targets the development of single-dopant transistors, single-molecule spintronic and electronic devices for data storage, single-molecule integrated single-photon sources and optical transistors based on plasmonic nanostructures [4].
For these purposes, we will exploit and develop novel advanced fabrication schemes, such as atom-by-atom processing in single-molecule electronic devices or nanopositioning tools to tailor light-matter interaction [5].
BIBLIOGRAPHY
[1] P.M. Koenraad and M.E. Flatté, Nature Mater. 10, 91 (2011).
[2] M. Fuechsle et al., Nature Nanotech. 7, 242 (2012).
[3] J. O’Brien et al., Nature Photon. 3, 687 (2009).
[4] D.E. Chang et al., Nature Phys. 3, 807 (2007).
[5] O. Benson, Nature 480, 193 (2011).

INO’s Experiments/Theoretical Study correlated:
Single Emitters for Quantum technologies