Quantum information at the interface of light with atomic ensembles and micromechanical oscillators. - Christine A. Muschik; Hanna Krauter; Klemens Hammerer; Eugene Polzik (Quantum Inf. Process., 2011)

Ramsey interferometry with generalized one-axis twisting echoes. - Marius Schulte; Victor J. Martínez-Lahuerta; Maja S. Scharnagl; Klemens Hammerer (Quantum, 2020)