Multiple-magnon excitations shape the spin spectrum of cuprate parent compounds

@ARTICLE{Betto2021,
	author = {Betto, Davide and Fumagalli, Roberto and Martinelli, Leonardo and Rossi, Matteo and Piombo, Riccardo and Yoshimi, Kazuyoshi and Di Castro, Daniele and Di Gennaro, Emiliano and Sambri, Alessia and Bonn, Doug and Sawatzky, George A. and Braicovich, Lucio and Brookes, Nicholas B. and Lorenzana, José and Ghiringhelli, Giacomo},
	title = {Multiple-magnon excitations shape the spin spectrum of cuprate parent compounds},
	year = {2021},
	journal = {Physical Review B},
	volume = {103},
	number = {14},
	doi = {10.1103/PhysRevB.103.L140409},
	url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85105533045&doi=10.1103%2fPhysRevB.103.L140409&partnerID=40&md5=573c83d35ea17fb2828122b8d2aec139},
	abstract = {Thanks to high resolution and polarization analysis, resonant inelastic x-ray scattering (RIXS) magnetic spectra of La2CuO4, Sr2CuO2Cl2 and CaCuO2 reveal a rich set of properties of the spin-1/2 antiferromagnetic square lattice of cuprates. The leading single-magnon peak energy dispersion is in excellent agreement with the corresponding inelastic neutron scattering measurements. However, the RIXS data unveil an asymmetric line shape possibly due to odd higher order terms. Moreover, a sharp bimagnon feature emerges from the continuum at (1/2,0), coincident in energy with the bimagnon peak detected in optical spectroscopy. These findings show that the inherently complex spin spectra of cuprates, an exquisite manifestation of quantum magnetism, can be effectively explored by exploiting the richness of RIXS cross sections. © 2021 American Physical Society.},
	type = {Article},
	publication_stage = {Final},
	source = {Scopus},
	note = {All Open Access, Green Open Access}
}