| Title: | Tunable pheromone interactions among microswimmers |
| Author(s): | Nakayama B; Nagase H; Takahashi H; Saito Y; Hatayama S; Makino K; Yamamoto E; Saiki T; |
| Address: | "Graduate School of Science and Technology, Keio University, Yokohama, Kanagawa 223-8522, Japan. Department of Electronics and Electrical Engineering, Keio University, Yokohama, Kanagawa 223-8522, Japan. Device Technology Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8568, Japan. Department of System Design Engineering, Keio University, Yokohama, Kanagawa 223-8522, Japan" |
| ISSN/ISBN: | 1091-6490 (Electronic) 0027-8424 (Print) 0027-8424 (Linking) |
| Abstract: | "Indirect interactions via shared memory deposited on the field ('field memory') play an essential role in collective motions. Some motile species, such as ants and bacteria, use attractive pheromones to complete many tasks. Mimicking these kinds of collective behavior at the laboratory scale, we present a pheromone-based autonomous agent system with tunable interactions. In this system, colloidal particles leave phase-change trails reminiscent of the process of pheromone deposition by individual ants, and the trails attract other particles and themselves. To implement this, we combine two physical phenomena: the phase change of a Ge(2)Sb(2)Te(5) (GST) substrate by self-propelled Janus particles (pheromone deposition) and the AC (alternating current) electroosmotic (ACEO) flow generated by this phase change (pheromone attraction). Laser irradiation causes the GST layer to crystalize locally beneath the Janus particles, owing to the lens heating effect. Under AC field application, the high conductivity of the crystalline trail causes a field concentration and generates ACEO flow, and we introduce this flow as an attractive interaction between the Janus particles and the crystalline trail. By changing the AC frequency and voltage, we can tune the attractive flow, i.e., the sensitivity of the Janus particles to the trail, and the isolated particles undergo diverse states of motion, from self-caging to directional motion. A swarm of Janus particles also shows different states of collective motion, including colony formation and line formation. This tunability enables a reconfigurable system driven by a pheromone-like memory field" |
| Keywords: | active colloids collective motion electrokinetic phase-change material; |
| Notes: | "PubMed-not-MEDLINENakayama, Bokusui Nagase, Hikaru Takahashi, Hiromori Saito, Yuta Hatayama, Shogo Makino, Kotaro Yamamoto, Eiji Saiki, Toshiharu eng JP22J14134/MEXT | Japan Society for the Promotion of Science (JSPS)/ 2023/02/23 Proc Natl Acad Sci U S A. 2023 Feb 28; 120(9):e2213713120. doi: 10.1073/pnas.2213713120. Epub 2023 Feb 22" |
