Portfolio: SONG Yong-Hong: Burning Realities 宋永红：灼热的现实

This Portfolio features 1) numerous essays on the artist (in both Chinese and English); 2) images of the artist\u27s selected works (with captions); and 3) a brief bibliographical account of the artist. (Jerry Wu\u2723).https://digital.kenyon.edu/zhoudocs/1242/thumbnail.jp

Deforming black holes with even multipolar differential rotation boundary

Motivated by the novel asymptotically global AdS$_4$ solutions with deforming horizon in [JHEP {\bf 1802}, 060 (2018)], we analyze the boundary metric with even multipolar differential rotation and numerically construct a family of deforming solutions with quadrupolar differential rotation boundary, including two classes of solutions: solitons and black holes. In contrast to solutions with dipolar differential rotation boundary, we find that even though the norm of Killing vector $\partial_t$ becomes spacelike for certain regions of polar angle $\theta$ when $\varepsilon>2$, solitons and black holes with quadrupolar differential rotation still exist and do not develop hair due to superradiance. Moreover, at the same temperature, the horizonal deformation of quadrupolar rotation is smaller than that of dipolar rotation. Furthermore, we also study the entropy and quasinormal modes of the solutions, which have the analogous properties to that of dipolar rotation.Comment: 18 pages, 21 figure

Observation of valley Landau-Zener-Bloch oscillations and pseudospin imbalance in photonic graphene

We demonstrate inter-valley Bloch oscillation (BO) and Landau-Zener tunneling (LZT) in an optically-induced honeycomb lattice with a refractive index gradient. Unlike previously observed BO in a gapped square lattice, we show non-adiabatic beam dynamics that are highly sensitive to the direction of the index gradient and the choice of the Dirac cones. In particular, a symmetry-preserving potential leads to nearly perfect LZT and coherent BO between the inequivalent valleys, whereas a symmetry-breaking potential generates asymmetric scattering, imperfect LZT, and valley-sensitive generation of vortices mediated by a pseudospin imbalance. This clearly indicates that, near the Dirac points, the transverse gradient does not always act as a simple scalar force as commonly assumed, and the LZT probability is strongly affected by the sublattice symmetry as analyzed from an effective Landau-Zener Hamiltonian. Our results illustrate the anisotropic response of an otherwise isotropic Dirac platform to real-space potentials acting as strong driving fields, which may be useful for manipulation of pseudospin and valley degrees of freedom in graphene-like systems

Methyl 4-(4-meth­oxy­phen­yl)-2-methyl-5-oxo-1,4,5,6,7,8-hexa­hydro­quinoline-3-carboxyl­ate

In the title compound, C19H21NO4, the dihydro­pyridine ring adopts a distorted screw-boat conformation. The fused cyclo­hexenone ring forms a slightly distorted envelope conformation. The dihedral angle between the mean planes of the benzene and heterocyclic rings is 86.1 (7)°. An intra­molecular C—H⋯O inter­action occurs. In the crystal, mol­ecules are linked by inter­molecular N—H⋯O hydrogen bonds, forming an infinite chain along the c axis

Ethyl 2-methyl-6-(propan-2-yl­amino)-4-sulfanyl­idene-3H,11H-pyrimido[1,6-c]quinazoline-1-carboxyl­ate

The title compound, C18H22N4O2S, contains a substituted pyrimidine ring fused to both a benzene ring and a substituted thioxopyrimidine ring. The pyrimidine and thioxopyrimidine rings adopt distorted chair conformations. In the crystal, adjacent mol­ecules are linked by pairs of N—H⋯S and N—H⋯O hydrogen bonds to generate centrosymmetric R 2 2(8) and R 2 2(16) loops, respectively. This combination leads to [100] chains of mol­ecules