冷却原子系における散逸を伴う非平衡量子多体物理

付記する学位プログラム名: 京都大学卓越大学院プログラム「先端光・電子デバイス創成学」京都大学新制・課程博士博士(理学)甲第24402号理博第4901号新制||理||1700(附属図書館)京都大学大学院理学研究科物理学・宇宙物理学専攻(主査)教授 川上 則雄, 教授 佐々 真一, 教授 高橋 義朗学位規則第4条第1項該当Doctor of ScienceKyoto UniversityDFA

Localization properties in disordered quantum many-body dynamics under continuous measurement

We study localization properties of continuously monitored dynamics and associated measurement-induced phase transitions in disordered quantum many-body systems on the basis of the quantum trajectory approach. By calculating the fidelity between random quantum trajectories, we demonstrate that the disorder and the measurement can lead to dynamical properties distinct from each other, although both have a power to suppress the entanglement spreading. In particular, in the large-disorder regime with weak measurement, we elucidate that the fidelity exhibits an anomalous power-law decay before saturating to the steady-state value. Furthermore, we propose a general method to access physical quantities for quantum trajectories in continuously monitored dynamics without resorting to postselection. It is demonstrated that this scheme drastically reduces the cost of experiments. Our results can be tested in ultracold atoms subject to continuous measurement and open the avenue to study dynamical properties of localization, which cannot be understood from the stationary properties of the entanglement entropy.Comment: 7+7 pages, 5+9 figures, To appear in Phys. Rev. B (Letter

Deep Reinforcement Learning-Based Channel Allocation for Wireless LANs with Graph Convolutional Networks

Last year, IEEE 802.11 Extremely High Throughput Study Group (EHT Study Group) was established to initiate discussions on new IEEE 802.11 features. Coordinated control methods of the access points (APs) in the wireless local area networks (WLANs) are discussed in EHT Study Group. The present study proposes a deep reinforcement learning-based channel allocation scheme using graph convolutional networks (GCNs). As a deep reinforcement learning method, we use a well-known method double deep Q-network. In densely deployed WLANs, the number of the available topologies of APs is extremely high, and thus we extract the features of the topological structures based on GCNs. We apply GCNs to a contention graph where APs within their carrier sensing ranges are connected to extract the features of carrier sensing relationships. Additionally, to improve the learning speed especially in an early stage of learning, we employ a game theory-based method to collect the training data independently of the neural network model. The simulation results indicate that the proposed method can appropriately control the channels when compared to extant methods

Stereoregular poly (methyl methacrylate) with double-clickable ω-end: synthesis and click reaction

Isotactic and syndiotactic poly(methyl methacrylate)s with orthogonally double-clickable terminal ends, that is, α,β-unsaturated esters for Michael addition-type thiol–ene reactions and azide or alkynyl groups for azide–alkyne click reactions, were prepared via a terminating reaction of stereospecific anionic polymerization with propargyl and 2-chloroethyl α-(chloromethyl)acrylates. The subsequent polymer modification via a double click reaction proceeded quantitatively in a one-pot system under ambient conditions. The facile and almost quantitative double-end-functionalization would open a new material design based on stereoregular PMMAs with controlled molecular weights.ArticlePolymer Chemistry.6(19):3601-3607(2015)journal articl

Verification of the relationship between full-body illusion indices

Full Body Illusion (FBI) is a phenomenon which changes over the sense of body ownership to other object and the illusion has been reported using various measurement indices (e.g., questionnaire , skin conductance response, and skin temperature). However, no studies have simultaneously measured these indices and it still remains unclear whether those indices capture the similar aspects of FBI. The present study investigate the relationship among those FBI indices. In this study, we presented an avatar to participants in a virtual room. We measured the questionnaires, skin conductance response, skin temperature, and drift as FBI indices. The result s showed that me asurement of the questionnaires and skin conductance response were reflected FBI, and the positive correlation was found between those two measurements questionnaire and skin conductance response ( rho = .5 5 , p < .05). Alternatively, no correlations were found among the other indices. Our results suggest that both the questionnaire and the skin conductance response reflect similar aspects of FBI