Description:

Title: Quantum sensing electric fields with trapped ions

Speaker: Jordi Mur-Petit, Instituto de Estructura de la Materia, IEM-CSIC, Madrid, Spain

Abstract: Formal developments in the context of quantum information theory, together with the superb experimental control on quantum systems attained in the last couple of decades, are giving rise to the appearance of a new field of research and development—quantum technologies—the use of quantum protocols and systems to enhance available technology or even develop totally new devices [1]. Within this field, quantum metrology or quantum sensing focuses in establishing the measurement uncertainties achievable according to quantum mechanics, to devise physical systems able to test them, and to design new measurement devices that translate these findings into practical applications [2].

Building on the exquisite control and precise detection methods available for trapped atomics ions [3], we have developed two proposals to use them as quantum probes of weak and/or short-pulsed electric fields. In our first proposal, we consider the measurement and stabilization of the carrier-envelope offset phase of a femtosecond frequency comb by multi-pulse quantum interferometry—a new interferometry protocol that uses a trapped ion as a nonlinear detector of the pulse-to-pulse phase variations of a fast train of laser pulses [4]. Our second work is an extension of ideas of quantum logic spectroscopy developed to probe atomic [5] and molecular [6] ions to probe polar molecules. Specifically, we rely on the electrostatic interaction between an ion and an electric dipole, together with quantum logic and state-dependent forces, to determine the electric dipole moment of a polar molecule by measuring the phase shift that this produces on a nearby probe ion [7].


References
[1] J.P. Dowling, G.J. Milburn, Phil. Trans. R. Soc. Lond. A 361, 1655-1674 (2003).
[2] V. Giovanetti, S. Lloyd, L. Maccone, Nature Photon. 5, 222-229 (2011).
[3] H. Häffner, C.F., Roos, R. Blatt, Phys. Rep. 469, 155–203 (2008); D. J. Wineland, Rev. Mod. Phys. 85, 1103 (2013).
[4] A. Cadarso, J. Mur-Petit, J.J. García-Ripoll, Phys. Rev. Lett. 112, 073603 (2014).
[5] P.O. Schmidt, T. Rosenband, C. Langer, W.M. Itano, J.C. Bergquist, D.J. Wineland, Science 309, 749 (2005).
[6] J. Mur-Petit, J.J. García-Ripoll, J. Pérez-Ríos, J. Campos-Martínez, M.I. Hernández, S. Willitsch, Phys. Rev. A 85, 022308 (2012).
[7] J. Mur-Petit, J.J. García-Ripoll, Appl. Phys. B 114, 283-294 (2014); Phys. Rev. A 91, 012504 (2015).