Bloch-Siegert Shift in a Hybrid Quantum Register: Quantification and Compensation

TL;DR

This paper investigates the Bloch-Siegert shift in hybrid quantum registers, specifically in NV centers in diamond, quantifies its effects, and demonstrates methods for its compensation to preserve quantum information.

Contribution

It provides a quantitative analysis of the Bloch-Siegert shift in NV centers and proposes strategies for its elimination in hybrid quantum systems.

Findings

Quantified the magnitude of the Bloch-Siegert shift in NV centers.

Demonstrated effective compensation techniques for the shift.

Showed that proper management of the shift preserves quantum information.

Abstract

Quantum registers that combine the attractive properties of different types of qubits are useful for many different applications. They also pose a number of challenges, often associated with the large differences in coupling strengths between the different types of qubits. One example is the non-resonant effect that alternating electromagnetic fields have on the transitions of qubits that are not targeted by the specific gate operation. The example being studied here is known as Bloch-Siegert shift. Unless these shifts are accounted for and, if possible, compensated, they can completely destroy the information contained in the quantum register. Here we study this effect quantitatively in the important example of the nitrogen vacancy (NV) center in diamond and demonstrate how it can be eliminated.