Building robust instruments capable of making interferometric measurements with precision beyond the standard quantum limit remains an important goal in many metrology laboratories. We describe here the basic concepts underlying spin squeezing experiments which allow one to surpass this limit. In principle it is possible to reach the so-called Heisenberg limit which constitutes an improvement in precision by a factor \sqrtN, where N is the number of particles on which the measurement is carried out. In particular, we focus on recent progress toward implementing spin squeezing with a cloud of beryllium ions in a Penning ion trap, via the geometric phase gate used more commonly for performing two-qubit entangling operations in quantum computing experiments.
Proceedings Title: AIP conference proceedings: "Quantum Africa 2010: Recent progress in the theoretical & experimental foundations of Quantum Technology
Conference Dates: September 20-23, 2010
Conference Location: Durban,
Pub Type: Conferences
ion trap, Penning trap, quantum metrology, spin squeezing