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arXiv · 1612.08748

Light-induced fractional quantum Hall phases in graphene

Areg Ghazaryan·Tobias Graß·Michael J. Gullans·Pouyan Ghaemi·Mohammad Hafezi
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Abstract

We show how to realize two-component fractional quantum Hall phases in monolayer graphene by optically driving the system. A laser is tuned into resonance between two Landau levels, giving rise to an effective tunneling between these two synthetic layers. Remarkably, because of this coupling, the interlayer interaction at non-zero relative angular momentum can become dominant, resembling a hollow-core pseudo-potential. In the weak tunneling regime, this interaction favors the formation of singlet states, as we explicitly show by numerical diagonalization, at fillings $ν=1/2$ and $ν=2/3$. We discuss possible candidate phases, including the Haldane-Rezayi phase, the interlayer Pfaffian phase, and a Fibonacci phase. This demonstrates that our method may pave the way towards the realization of non-Abelian phases, as well as the control of topological phase transitions, in graphene quantum Hall systems using optical fields and integrated photonic structures.

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Areg Ghazaryan, Tobias Graß, Michael J. Gullans, Pouyan Ghaemi, Mohammad Hafezi. 2017-09-15. Light-induced fractional quantum Hall phases in graphene. https://doi.org/10.1103/physrevlett.119.247403

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