Manipulation of Non-classical Atomic Spin States

TL;DR

This paper demonstrates the manipulation of non-classical atomic spin states, including generating squeezed states and observing anisotropic quantum noise rotation, advancing quantum measurement techniques.

Contribution

It introduces a method to manipulate non-classical spin states using off-resonant light pulses, showing noise anisotropy rotation, which is novel for quantum state control.

Findings

Successful generation of squeezed spin states

Observation of anisotropic quantum noise rotation

Potential applications in quantum tomography and precision measurement

Abstract

We report successful manipulation of non-classical atomic spin states. We generate squeezed spin states by a spin quantum nondemolition measurement, and apply an off-resonant circularly-polarized light pulse to the atoms. By changing the pulse duration, we have clearly observed a rotation of anisotropic quantum noise distribution in good contrast with the case of manipulation of a coherent spin state where the quantum noise distribution is always isotropic. This is an important step for quantum state tomography, quantum swapping, and precision spectroscopic measurement.