Switchable damping for a one-particle oscillator

Area of Science:

• Quantum physics
• Atomic, molecular, and optical physics

Background:

• Penning traps are crucial for high-precision measurements of fundamental electron properties.
• Previous measurements were limited by the backaction of detection motion, affecting sensitivity.
• Controlling electron oscillation damping is key to overcoming these limitations.

Purpose of the Study:

• To demonstrate a method for switching the axial damping rate of a one-electron oscillator in a Penning trap.
• To enable quantum nondemolition detection of electron cyclotron and spin states with improved precision.
• To reduce the linewidth of the electron's cyclotron transition.

Main Methods:

• Utilizing a Penning trap to confine a single electron oscillating along the magnetic field axis.
• Implementing a novel switching mechanism to control the axial damping rate.
• Applying strong axial damping for detection and weak axial damping to mitigate backaction.

Main Results:

• Successfully demonstrated the ability to switch the damping rate of the electron oscillator.
• Achieved quantum nondemolition detection of the electron's cyclotron and spin quantum states.
• The developed switch reduces the linewidth of the cyclotron transition by two orders of magnitude.

Conclusions:

• The switchable damping rate provides a powerful new tool for electron quantum state detection.
• This advancement significantly enhances the precision of measurements for fundamental electron properties.
• The technique opens avenues for more sensitive quantum nondemolition measurements in trapped-ion systems.