Related Experiment Video
Updated: Nov 5, 2025
05:39
Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
9.9K
Entanglement Transition in a Monitored Free-Fermion Chain: From Extended Criticality to Area Law.
O Alberton1, M Buchhold1, S Diehl1
1Institut für Theoretische Physik, Universität zu Köln, D-50937 Cologne, Germany.
Physical Review Letters
|May 14, 2021
Summary
Continuous monitoring of free fermions reveals a novel entanglement phase transition. Weak monitoring leads to subextensive entanglement growth, while strong monitoring induces a quantum Zeno-like state, crucial for phase transitions.
Area of Science:
- Quantum physics
- Condensed matter theory
- Many-body systems
Background:
- Continuous monitoring profoundly impacts quantum systems.
- Understanding entanglement dynamics is key to quantum information science.
- Free fermions provide a fundamental model for quantum phenomena.
Purpose of the Study:
- To investigate the quantum trajectory dynamics of free fermions under continuous monitoring.
- To identify novel dynamical regimes and entanglement transitions.
- To explore the role of measurement strength in quantum phase transitions.
Main Methods:
- Analysis of quantum trajectory dynamics.
- Characterization of entanglement growth under weak and strong monitoring.
- Investigation of critical phenomena and finite-size corrections.
Main Results:
- A novel regime of subextensive entanglement growth under weak monitoring, exhibiting emergent conformal invariance.
- A transition to a quantum Zeno-like area-law regime under strong monitoring.
- Logarithmic finite-size corrections near the critical point, suggesting a Berezinskii-Kosterlitz-Thouless mechanism.
Conclusions:
- Continuous monitoring drives unconventional entanglement transitions in free fermion systems.
- The strength of measurement is critical for the occurrence of these phase transitions.
- The findings offer insights into measurement-induced dynamics and quantum criticality.
Related Concept Videos
01:12Fermi Level Dynamics
428
The vacuum level denotes the energy threshold required for an electron to escape from a material surface. It is usually positioned above the conduction band of a semiconductor and acts as a benchmark for comparing electron energies within various materials.
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
428
01:10First Law: Particles in One-dimensional Equilibrium
7.4K
Newton's first law of motion states that a body at rest remains at rest, or if in motion, remains in motion at constant velocity, unless acted on by a net external force. It also states that there must be a cause for any change in velocity (a change in either magnitude or direction) to occur. This cause is a net external force. For example, consider what happens to an object sliding along a rough horizontal surface. The object quickly grinds to a halt, due to the net force of friction. If...
7.4K
01:23Atomic Nuclei: Nuclear Relaxation Processes
864
In the absence of an external magnetic field, nuclear spin states are degenerate and randomly oriented. When a magnetic field is applied, the spins begin to precess and orient themselves along (lower energy) or against (higher energy) the direction of the field. At equilibrium, a slight excess population of spins exists in the lower energy state. Because the direction of the magnetic field is fixed as the z-axis, the precessing magnetic moments are randomly oriented around the z-axis.
864
03:25Free Energy Changes for Nonstandard States
12.3K
The free energy change for a process taking place with reactants and products present under nonstandard conditions (pressures other than 1 bar; concentrations other than 1 M) is related to the standard free energy change according to this equation:
12.3K
01:18First Law: Particles in Two-dimensional Equilibrium
10.1K
Recall that a particle in equilibrium is one for which the external forces are balanced. Static equilibrium involves objects at rest, and dynamic equilibrium involves objects in motion without acceleration; but it is important to remember that these conditions are relative. For instance, an object may be at rest when viewed from one frame of reference, but that same object would appear to be in motion when viewed by someone moving at a constant velocity.
Newton's first law tells us about...
Newton's first law tells us about...
10.1K
02:39Phase Transitions: Melting and Freezing
13.6K
Heating a crystalline solid increases the average energy of its atoms, molecules, or ions, and the solid gets hotter. At some point, the added energy becomes large enough to partially overcome the forces holding the molecules or ions of the solid in their fixed positions, and the solid begins the process of transitioning to the liquid state or melting. At this point, the temperature of the solid stops rising, despite the continual input of heat, and it remains constant until all of the solid is...
13.6K