Decoherence-Free Rotational Degrees of Freedom for Quantum Applications

TL;DR

This paper introduces a method using spherical t-designs to create solid objects with rotational degrees of freedom that are resistant to decoherence, enabling long-lived quantum states for sensing and quantum information.

Contribution

It presents a novel approach to constructing decoherence-resistant rotational quantum states using spherical t-designs, enhancing quantum sensing and information processing capabilities.

Findings

Enhanced ratio of signal to decoherence rate with complex shapes

Long-lived macroscopic quantum superpositions achieved

Robust entanglement generation between solids demonstrated

Abstract

We employ spherical $t$-designs for the systematic construction of solids whose rotational degrees of freedom can be made robust to decoherence due to external fluctuating fields while simultaneously retaining their sensitivity to signals of interest. Specifically, the ratio of signal phase accumulation rate from a nearby source to the decoherence rate caused by fluctuating fields from more distant sources can be incremented to any desired level by using increasingly complex shapes. This allows for the generation of long-lived macroscopic quantum superpositions of rotational degrees of freedom and the robust generation of entanglement between two or more such solids with applications in robust quantum sensing and precision metrology as well as quantum registers.