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Entanglement Phase Transition with Spin Glass Criticality
Jeremy Côté1, Stefanos Kourtis1
1Département de physique and Institut quantique, Université de Sherbrooke, Sherbrooke, Québec J1K 2R1, Canada.
Physical Review Letters
|July 1, 2022
Summary
Researchers discovered an entanglement phase transition in quantum circuits, mapping it to a spin glass model. This reveals critical behavior in quantum systems and establishes a new statistical mechanics theory for entanglement phase transitions.
Area of Science:
- Quantum Information Science
- Condensed Matter Physics
- Statistical Mechanics
Background:
- Entanglement is a key resource in quantum information.
- Phase transitions in quantum systems are crucial for understanding complex quantum behaviors.
- Quantum circuits offer a platform for simulating many-body quantum phenomena.
Purpose of the Study:
- To define and investigate an entanglement phase transition in random Clifford quantum circuits.
- To establish an exact mapping between the quantum circuit output state and a spin glass model.
- To identify and characterize the nature of the entanglement phases and the transition point.
Main Methods:
- Defining an ensemble of random Clifford quantum circuits.
- Mapping the circuit's output state to the ground space of a spin glass model.
- Utilizing an order parameter accessible on quantum hardware to identify entanglement phases.
- Locating the critical transition point and evaluating critical exponents.
Main Results:
- An entanglement phase transition was observed between two volume-law entangled phases as a function of measurement rate.
- The quantum circuit setup exactly maps to the ground space of a spin glass model.
- Spin glass criticality was identified, with a critical exponent evaluated.
- An order parameter measurable on a quantum chip was used to characterize the entanglement phases.
Conclusions:
- The study establishes an exact statistical mechanics theory for entanglement phase transitions in quantum circuits.
- The findings reveal a direct connection between entanglement phase transitions and spin glass criticality.
- The developed methods allow for experimental investigation of these phenomena on quantum hardware.
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