Observing Quantum Phase transitions in a moving frame
02/24 2022 Seminar
- Title Observing Quantum Phase transitions in a moving frame
- Speaker Jinwu Ye (Mississippi State Univ./West Lake Univ.)
- Date 2022年02月24日 10:00
- Venue ITP New building 6420
The important role of Lorentz transformation (LT) and invariance in relativistic quantum field theory is well appreciated and understood. At a low velocity, the LT just reduces to the Galileo transformation (GT). While many body systems in materials or cold atom systems are non-relativistic. Unfortunately, the possible effects of GT in many body systems were poorly understood. In this work, we explore its dramatic effects near quantum phase transitions (QPT) which are among the most fantastic phenomena in Nature. We show that observing them in different inertial frames may lead to novel quantum phases through new quantum phase transitions. We demonstrate this new effect by studying one of the simplest QPTs: Superfluid (SF)-Mott transitions of interacting bosons in a square lattice in a frame moving with a constant velocity $ c $. We develop effective actions in the moving frame, then explore them by applying various methods such as field theory renormalization group, charge-vortex duality and scaling analysis. The intrinsic interplay between the Galileo transformation and symmetry breaking in many body quantum systems are analyzed. Contrast to the Doppler shifts in a relativistic quantum field theory and Unruh effects in an accelerating observer are made. Experimental detections in the moving frame are also discussed.