Inverse Mpemba Effect Demonstrated on a Single Trapped Ion Qubit.

Area of Science:

• Quantum physics
• Thermodynamics
• Quantum information science

Background:

• The Mpemba effect describes hot water freezing faster than cold water under identical conditions.
• This phenomenon remains incompletely understood, with proposed explanations involving convection, evaporation, and hydrogen bonding.
• Investigating quantum analogs can elucidate fundamental principles and potentially reveal new physical mechanisms.

Purpose of the Study:

• To explore a quantum mechanical analog of the Mpemba effect.
• To investigate anomalous relaxation dynamics in the simplest quantum system, a qubit.
• To experimentally verify the quantum Mpemba effect in a trapped ion system.

Main Methods:

• Theoretical modeling of a qubit system undergoing thermalization.
• Numerical simulations to analyze relaxation dynamics.
• Experimental implementation using a single ^{88}Sr^{+} trapped ion qubit.

Main Results:

• A quantum analog of the Mpemba effect was observed, termed the inverse Mpemba effect.
• Cold qubits were found to reach hot temperatures faster than hot qubits.
• A strong version of the effect was demonstrated, with cold qubits heating exponentially faster due to quantum interference.

Conclusions:

• The quantum Mpemba effect is a fundamental phenomenon arising from quantum mechanical interference.
• This effect is observable in simple, coherent quantum systems like trapped ion qubits.
• Understanding this anomalous relaxation is crucial for designing and operating quantum information processing devices.