Nanophysics Seminar

Dr. Markus Parzefall, ETH Zürich
Light from van der Waals quantum tunneling devices

The ability of tunneling electrons to excite optical modes by means of inelastic electron tunneling has been known and investigated for four decades [1]. With the recent demonstrations of light emitting antenna-coupled tunnel junctions a new kind of nanoscopic light source was developed, accompanied by an advanced level of control and understanding [2-4]. The prospects of tunnel junctions as photon sources are manifold as they hold promise for ultrahigh modulation bandwidths and small footprint.

In this talk I will present a novel platform for the investigation of interactions between electromagnetic modes and tunneling electrons – van der Waals quantum tunneling devices [5]. We assemble and investigate novel types of hybrid vertical tunneling heterostructures comprised of combinations of gold (plasmonic metal), hexagonal boron nitride (two-dimensional wide bandgap insulator), and graphene (two-dimensional semimetal).  This allows us to tailor the electronic properties of tunneling devices. In addition, we demonstrate the resonant enhancement of photon emission by coupling said heterostructures to nanocube antennas.

References

[1] J. Lambe & S. L. McCarthy, Phys. Rev. Lett. 37, 923 (1976).
[2] M. Parzefall, P. Bharadwaj, A. Jain, T. Taniguchi, K. Watanabe & L. Novotny, Nature Nanotech. 10, 1058-1063 (2015).
[3] J. Kern, R. Kullock, J. Prangsma, M. Emmerling, M. Kamp & B. Hecht, Nature Phot. 9, 582-586 (2015).
[4] H. Qian, S.-W. Hsu, K. Gurunatha, C. T. Riley, J. Zhao, D. Lu, A. R. Tao & Z. Liu, Nature Phot. 12, 485-488 (2018).
[5] M. Parzefall, A. Szabo, T. Taniguchi, K. Watanabe, M. Luisier & L. Novotny, arxiv:1804.06163 [cond-mat.mes-hall] (2018).

Thursday, 20.12.18

11:30 h - 12:30 h

Geschwister-Scholl-Platz 1