Time, momentum, and energy resolved pump-probe tunneling spectroscopy of two-dimensional electron systems

Autor: H. M. Yoo, M. Korkusinski, D. Miravet, K. W. Baldwin, K. West, L. Pfeiffer, P. Hawrylak, R. C. Ashoori
Jazyk: angličtina
Rok vydání: 2023
Předmět:
Zdroj: Nature Communications, Vol 14, Iss 1, Pp 1-6 (2023)
Druh dokumentu: article
ISSN: 2041-1723
DOI: 10.1038/s41467-023-43268-1
Popis: Abstract Real-time probing of electrons can uncover intricate relaxation mechanisms and many-body interactions in strongly correlated materials. Here, we introduce time, momentum, and energy resolved pump-probe tunneling spectroscopy (Tr-MERTS). The method allows the injection of electrons at a particular energy and observation of their subsequent decay in energy-momentum space. Using Tr-MERTS, we visualize electronic decay processes, with lifetimes from tens of nanoseconds to tens of microseconds, in Landau levels formed in a GaAs quantum well. Although most observed features agree with simple energy-relaxation, we discovered a splitting in the nonequilibrium energy spectrum in the vicinity of a ferromagnetic state. An exact diagonalization study suggests that the splitting arises from a maximally spin-polarized state with higher energy than a conventional equilibrium skyrmion. Furthermore, we observe time-dependent relaxation of the splitting, which we attribute to single-flipped spins forming skyrmions. These results establish Tr-MERTS as a powerful tool for studying the properties of a 2DES beyond equilibrium.
Databáze: Directory of Open Access Journals