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arXiv:2309.12751

Coherent control of orbital wavefunctions in the quantum spin liquid $Tb_{2}Ti_{2}O_{7}$

Roman Mankowsky, Müller, M., Mathias Sander, Serhane Zerdane, Xin Liu, Danylо Babich, Hiroki Ueda, Yongqing Deng, Winkler, R., Benjamin H. Strudwick, Matteo Savoini, F. Giorgianni, Steven L. Johnson, Ekaterina V. Pomjakushina, P. Beaud, Thomas Fennel, Henrik Till Lemke, U. Staub

Published Sep 22, 2023• 0 citations
arXivHTMLPDF

Abstract

Resonant driving of electronic transitions with coherent laser sources creates quantum coherent superpositions of the involved electronic states. Most time-resolved studies have focused on gases or isolated subsystems embedded in insulating solids, aiming for applications in quantum information. Here, we demonstrate coherent control of orbital wavefunctions in pyrochlore $Tb_{2}Ti_{2}O_{7}$, which forms an interacting spin liquid ground state. We show that resonant excitation with a strong THz pulse creates a coherent superposition of the lowest energy Tb 4f states before the magnetic interactions eventually dephase them. The coherence manifests itself as a macroscopic oscillating magnetic dipole, which is detected by ultrafast resonant x-ray diffraction. The induced quantum coherence demonstrates coherent control of orbital wave functions, a new tool for the ultrafast manipulation and investigation of quantum materials.

DOI
10.48550/arxiv.2309.12751

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