Implementation schemes for unsharp measurements with trapped ions

TL;DR

This paper proposes experimental schemes for implementing unsharp measurements on trapped ion qubits using weak entanglement and projective measurements, analyzing error effects on various applications.

Contribution

It introduces practical methods for unsharp measurements in trapped ions, combining standard quantum logic operations with projective measurements on an auxiliary ion.

Findings

Schemes enable unsharp measurements with trapped ions

Error analysis shows robustness of the methods

Potential applications in quantum information processing

Abstract

Unsharp POVM measurements allow a variety of measurement applications which minimally disrupt the state of the quantum system. Experimental schemes are proposed for implementing unsharp measurements on the qubit levels of a trapped ion. The schemes rely on introducing weak entanglement between the state of a target ion, and that of an auxiliary ion, using standard ion trap quantum logic operations, and then realizing an unsharp measurement through projective measurement on the auxiliary atom. We analyze common sources of error and their effect on different applications of unsharp measurements.