Nonreciprocal Directional Dichroism Induced by the Quantum Metric Dipole

Journal Article · 06 June 2019 · Physical Review Letters

DOI: https://doi.org/10.1103/physrevlett.122.227402 · OSTI ID:1611832

Gao, Yang ^[1]; Xiao, Di ^[2]

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1. Carnegie Mellon Univ., Pittsburgh, PA (United States); DOE/OSTI
2. Carnegie Mellon Univ., Pittsburgh, PA (United States)

We identify the quantum metric dipole as the geometric origin of the nonreciprocal directional dichroism which describes the change in the refractive index upon reversing the light propagation direction. Specifically, we find that the static limit of the nonreciprocal directional dichroism corresponds to a quadrupolar transport current from the quantum metric dipole, in response to a quadrupolar electric field. Moreover, at a finite frequency, we demonstrate that the steepest slope of the averaged quantum metric dipole gives rise to a peak in the differential refractive index between counterpropagating lights. Lastly, we illustrate both features in a low-energy model.

• Research Organization: Univ. of Washington, Seattle, WA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: SC0012509
• OSTI ID: 1611832
• Journal Information: Physical Review Letters, Journal Name: Physical Review Letters Journal Issue: 22 Vol. 122; ISSN 0031-9007
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English