Sine-square deformation of one-dimensional critical systems
e-mail: oshikawa@issp.u-tokyo.ac.jp
Sine-square deformation (SSD) is one example of smooth boundary conditions with significantly smaller finite-size effects than open boundary conditions. In one-dimensional chains with SSD, the interaction strength decreases from the center to the edges according to the sine-square function. Thus, the Hamiltonian describing such a system is inhomogeneous and lacks translational symmetry. Nevertheless, previous studies have revealed that the SSD leaves the ground state of a uniform chain with periodic boundary conditions (PBC) almost unchanged for critical systems. In particular, I showed in [1,2,3] that the correspondence is exact for critical XY and quantum Ising chains. The same correspondence between SSD and PBC holds for Dirac fermions in 1+1 dimension and more general conformal field theories. In this talk, I will review these results. If time permits, I will also talk about some recent developments.
[1] H. Katsura, J. Phys. A: Math. Theor. 44, 252001 (2011).[2] H. Katsura, J. Phys. A: Math. Theor. 45, 115003 (2012).
[3] I. Maruyama, H. Katsura, T. Hikihara, Phys. Rev. B 84, 165132 (2011).
Chair: Eun Gook Moon
This event is jointly organized by the Korea Institute for Advanced Study and the University of Tokyo. “Correlated Electrons Virtual International Seminars (CEVIS)” https://sites.google.com/view/cevis2020/home