6 papers
Frustration-free free fermions
Seishiro Ono, Rintaro Masaoka, Haruki Watanabe +1
We develop a general theory of frustration-free free-fermion systems and derive the necessary and sufficient conditions for such Hamiltonians. Assuming locality and translation inv…
Frustration-free free fermions and beyond
Rintaro Masaoka, Seishiro Ono, Hoi Chun Po +1
Frustration-free Hamiltonians provide pivotal models for understanding quantum many-body systems. In this paper, we establish a general framework for frustration-free fermionic sys…
Rigorous lower bound on dynamical exponents in gapless frustration-free systems
Rintaro Masaoka, Tomohiro Soejima, Haruki Watanabe
This work rigorously establishes a universal lower bound for the dynamical exponent in frustration-free quantum many-body systems whose ground states exhibit power-law deca…
conformal field theory in quadratic band touching
Rintaro Masaoka
Quadratic band touching in fermionic systems defines a universality class distinct from that of linear Dirac points, yet its characterization as a quantum critical point remains in…
Rigorous lower bound of the dynamical critical exponent of the Ising model
Rintaro Masaoka, Tomohiro Soejima, Haruki Watanabe
We study the kinetic Ising model under Glauber dynamics and establish an upper bound on the spectral gap for finite systems. This bound implies the critical exponent inequality $z…
Quadratic dispersion relations in gapless frustration-free systems
Rintaro Masaoka, Tomohiro Soejima, Haruki Watanabe
Recent case-by-case studies revealed that the dispersion of low energy excitations in gapless frustration-free Hamiltonians is often quadratic or softer. In this work, we argue tha…