Counterroating incommensurate magnetic order and strong quantum fluctuations in the honeycomb layers of $\rm NaNi_2BiO_6$

A. Scheie,1 K. Ross,2, 3 E. Seibel,4 J. A. Rodriguez-Rivera,5, 6 J. A. Tang,7 Yi Li,1 R. J. Cava,4 and C. Broholm1, 5, 8 Institute for Quantum Matter and Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218 Department of Physics, Colorado State University, Fort Collins, CO 80523 Quantum Materials Program, Canadian Institute for Advanced Research (CIFAR), Toronto, Ontario M5G 1Z8, Canada Department of Chemistry, Princeton University, Princeton, NJ 08544 NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899 Department of Materials Sciences, University of Maryland, College Park, MD 20742 Department of Chemistry, Johns Hopkins University, Baltimore, MD 21218 Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, MD 21218 (Dated: July 10, 2018)