Long-lived population inversion in resonantly driven excitonic antiferromagnet

Abstract

Van der Waals magnets are an emerging material family for investigating light-matter interactions and spin-correlated excitations. Here, we report the discovery of a photo-induced state with a lifetime of 17 ps in the van der Waals antiferromagnet NiPS${}_3$, which appears exclusively with resonant pumping at 1.476 eV in the antiferromagnetic state. The long-lived state comes with a negative photoconductivity, a characteristic optical response of population inversion. Our findings demonstrate a promising pathway to potentially achieve long-lived lasing at terahertz frequencies in reduced dimensions.

6 pages, 3 figures. Accepted for publication in Physical Review Letters

References in corpus (9)

• Ising-Type Magnetic Ordering in Atomically Thin FePS3
• Suppression of magnetic ordering in XXZ-type antiferromagnetic monolayer NiPS3
• Trion induced negative photoconductivity in monolayer MoS2
• Semiconducting-to-metallic photoconductivity crossover and temperature-dependent Drude weight in graphene
• Exciton-driven antiferromagnetic metal in a correlated van der Waals insulator
• Magnetically brightened dark electron-phonon bound states in a van der Waals antiferromagnet
• Magnetically propagating Hund's exciton in van der Waals antiferromagnet NiPS3
• A Hubbard exciton fluid in a photo-doped antiferromagnetic Mott insulator
• Exciton-spin interactions in antiferromagnetic charge-transfer insulators

Cited by in corpus (1)

• Characteristic exciton energy scales in antiferromagnetic NiPS${}_3$