Two-Qubit Entanglement Generation through Non-Hermitian Hamiltonians Induced by Repeated Measurements on an Ancilla

Area of Science:

• Quantum mechanics
• Quantum information science
• Condensed matter physics

Background:

• Implementing non-Hermitian Hamiltonian dynamics in quantum systems is challenging due to trace-preserving system-environment interactions.
• A recent scheme proposed engineering non-Hermitian Hamiltonians via repetitive measurements on an ancillary qubit.

Purpose of the Study:

• To demonstrate the effectiveness of a proposed protocol for engineering non-Hermitian Hamiltonians.
• To apply this protocol to physically relevant multi-spin models.
• To explore the simulation of quantum dynamics described by non-Hermitian Hamiltonians.

Main Methods:

• Applying a protocol of repetitive measurements on an ancillary qubit to engineer effective non-Hermitian Hamiltonians.
• Investigating the dynamics of multi-spin models under these engineered Hamiltonians.
• Developing a physical scenario for simulating non-Hermitian quantum dynamics.

Main Results:

• The engineered non-Hermitian Hamiltonian effectively drives multi-spin systems to a maximally entangled stationary state.
• Demonstrated the protocol's effectiveness on physically relevant models.
• Reported a new method for simulating quantum systems with given non-Hermitian Hamiltonians.

Conclusions:

• The proposed measurement-based protocol is effective for engineering non-Hermitian dynamics in quantum systems.
• This approach facilitates reaching highly entangled states and offers new avenues for quantum simulations.
• The findings have broad implications for quantum information processing and fundamental physics.