Physical Chemistry Seminar: Dr. Herr vander Zant, (TUDelft)

April 23, 2018 - 03:00 PM - 04:00 PM
Speaker: 
Host:Gai
Location: 
Carol Lynch Lecture Hall Chemistry Complex

Single-molecule quantum transport for electronic component s

 


Herre S.J. van der Zant Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ, Delft, The Netherlands  (E-mail: h.s.j.vanderzant@tudelft.nl)  In downscaling the size of electronic components, molecules are viewed as promising alternatives as they can have additional functionality built-in by chemical design. We have developed several techniques to create solid-state, single-molecule devices [1] in which molecules are deposited from solution. These include mechanical controlled break junctions, molecular transistors made by a self-breaking electromigration technique, and room-temperature stable molecular transistors by electroburning of few-layer graphene. With these techniques in place, we investigate the quantum transport properties of a wide variety of molecules, with a special emphasis to use the intrinsic molecular structure (e.g. the orbital structure or spin degrees of freedom) to create electronic functionalities. Functionality can be based on quantum interference effects [2] or on the creation of barriers within the molecule over which substantial voltage drops occur when biasing the molecules. In this way, quantum-interference and spin-crossover switches, resonant tunneling devices [3] and single-molecule rectifiers [4] can be created.    Molecule and diode mechanism: Chemical structure (left panel) of the molecule used in our studies and its energy diagram (right panel), with the right half being lower in energy than the left one due to the electron withdrawing character of the fluorine substituents. At zero bias, transport is blocked. For one bias polarity the two levels are pulled further away from each other (blocking transport even more), while for the opposite bias polarity the levels are brought closer together thereby facilitating transport.

  Research supported by the national funding agencies (NWO/OCW) and by an ERC Advanced grant (Mols@Mols). References: [1]     M.L. Perrin, E. Burzurí and H.S.J. van der Zant, Chem. Soc. Rev. 44 (2015) 902–919.  [2]     M. Koole et al., Nano Letters 15 (2015) 5569–5573; H. Lissau et al., Nature Communications 6 (2015) 10233; R. Frisenda et al., Nature Chemistry 8 (2016) 1099–1104. [3]     M.L. Perrin et al., Nature Nanotechnology 9 (2014) 830–834. [4]     M.L. Perrin et al., Journal of Physical Chemistry C119 (2015) 5697-5702; M.L. Perrin et al., Nanoscale 8 (2016) 8919-8923; M.L. Perrin et al., Physical Chemistry Chemical Physics 19 (2017) 29187–29194.






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