Ion trap with attached molecular beam line 


Fernandez-Gonzalvo, X., Keller, M., A fully fiber-integrated ion trap for portable quantum technologies. Science Reports, 13, 523 (2023). 


Barontini, G., Blackburn, L., Boyer, V., Butuc-Mayer, F., Calmet, X., Crespo López-Urrutia, J. R., Curtis, E. A., Darquié, B., Dunningham, J., Fitch, N. J., Morgan, E. M., Georgiou, K., Gill, P., Godun, R. M., Goldwin, J., Guarrera, V., Harwood, A. C., Hill, I. R., Hendricks, R. J.,  Jeong, M., Johnson, M. Y. H., Keller, M., Kozhiparambil Sajith, L. P., Kuipers, F., Margolis, H. S., Mayo, C., Newman, P., Parsons, A. O., Prokhorov, L., Robertson, B. I., Rodewald, J.,  Safronova, M. S., Sauer, B. E., Schioppo, M., Sherill, N., Stadnik, Y. V., Szymaniec, K., Tarbutt, M. R., Thompson, R. C., Tofful, A., Tunesi, J., Vecchio, A., Wang, Y., & Worm, S., Measuring the stability of fundamental constants with a network of clocks. EPJ Quantum Technology, 9(12) (2022).

Keller, M., Cavity-QED with single trapped ions. Contemporary Physics, 63(1) (2022).

Keller, M., & Ward, T., Generation of time-bin-encoded photons in an ion-cavity system. New Journal of Physics, 24, 123028 (2022). New Journal of Physics, DOI 10.1088/1367-2630/aca9ee (2022)

Teixeira, W., Keller, M., & Semião, F., Pulsed multireservoir engineering for a trapped ion with applications to state synthesis and quantum Otto cycles. New Journal of Physics, 24, 023027 (2022). New Journal of Physics, DO! 10.1088/1367-2630/ac5131 (2022)


Barontini, G., Boyer, V., Calmet, X., Fitch, N. J., Forgan, E. M., Godun, R. M., Goldwin, J., Guarrera, V., Hill, I. R., Jeong, M., Keller, M., Kuipers, F., Margolis, H. S., Newman, P., Prokhorov, L., Rodewald, J., Sauer, B. E., Schioppo, M., Sherrill, N., Tarbutt, M. R., Vecchio, A., & Worm, S., QSNET, a network of clocks for measuring the stability of fundamental constants. Proceedings 11881, Quantum Technology: Driving commercialisation of an Enabling science II (2021)


Blackburn, L., & Keller, M., The effect of the electric trapping field on state-selective loading of molecules into rf ion traps. Scientific Reports, 10, 18449 (2020).

Christoforou, C. M., Pignot, C., Kassa, E., Takahashi, H., & Keller, M., Enhanced ion–cavity coupling through cavity cooling in the strong coupling regime. Scientific Reports, 10, 15693 (2020).
The datasets for the figures are available on Figshare.

Peerzada, A., Jobson, C. M., Kassa, E., Morphew, J., Fernandez-Gonzalvo, X., & Keller, M., Versatile optical fiber feedthroughs for ultra-high vacuum applications. Vacuum,180, ISSN 0042-207X (2020). 

Savelli, G., Colonna, J-P., Keller, M., Coudrain, P., Wendler, D., Goeppert, J., Manoli, Y., Faucherand, P., & Royer, A., Integrated thermoelectric sensors based on quantum dot superlattice for thermal management applications. Journal of Physics D: Applied Physics, 53(44) (2020).  Journal of Physics D: Applied Physics, Volume 53, Number 44 (2020)

Takahashi, H., Kassa, E., Christoforou, C., & Keller, M., Strong coupling of a single ion to an optical cavity. Physical Review Letters, 124(1) (2020).

Walker, T., Kashanian, S., Ward, T., & Keller, M., Improving the indistinguishability of single photons from an ion-cavity system. Physical Review A, 102(3) (2020).
The datasets for the figures are available here.


Gardner, A., Softley, T., & Keller, M., Multi-photon ionisation spectroscopy for rotational state preparation of N+2.
Scientific Report, 9, 506 (2019).


Foot, C. J., Trypogeorgos, D., Bentine, E., Gardner, A., & Keller, M., Two-frequency operation of a Paul trap to optimise confinement of two species of ions.
International Journal of Mass Spectrometry, 430, 117-125 (2018).

Kassa, E., Takahashi, H., Christoforou, C., & Keller, M., Precise positioning of an ion in an integrated Paul trap-cavity system using radiofrequency signals. Journal of Modern Optics, 65(5-6), 520-528 (2018).

Wagner, R., Guzman, F., Chijioke, A., Gulati, G., Keller, M., & Shaw, G., Direct measurement of radiation pressure and circulating power inside a passive optical cavity. Optica Express, 26(18) (2018). Optics Express 26, 23492-23506 (2018).

Walker, T., Miyanishi, K., Ikuta, R., Takahashi, H., Vartabi Kashanian, S., Tsujimoto, Y., Hayasaka, K., Yamamoto, T., Imoto, N., & Keller, M., Long-distance single photon transmission from a trapped ion via quantum frequency conversion. Physical Review Letters, 120(20) (2018).


Gulati, G. K., Takahashi, H., Podoliak, N., Horak, P., & Keller, M., Fiber cavities with integrated mode matching optics.
Scientific Reports 7, 5566 (2017).

Podoliak, N., Takahashi, H., Keller, M., & Horak, P.,  Harnessing the mode mixing in optical fiber-tip cavities. Journal of Physics B: Atomic, Molecular and Optical Physics, 50 (2017).

Takahashi, H., Kassa, E., Christoforou, C., & Keller, M., Cavity-induced anticorrelated photon-emission rates of a single ion. Physical Review A, 96(2) (2017).

Takahashi, H., Nevado, P., & Keller, M., Mølmer–Sørensen entangling gate for cavity QED systems. Journal of Physics B: Atomic, Molecular and Optical Physics, 50 (2017). 


Begley, S., Vogt, M., Kaur Gulati, G., Takahashi, H., & Keller M., Optimized multi-ion cavity coupling.
Physical Review Letters, 116(22), 223001 (2016).

Márquez Seco, A., Takahashi, H., & Keller, M., Novel ion trap design for strong ion-cavity coupling. Atoms, 4(2) (2016).

Podoliak, N., Takahashi, H., Keller, M., & Horak, P., Comparative numerical studies of ion traps with integrated optical cavities. Physical Review Applied, 6(4) (2016).


Deb, N., Pollum, L. L., Smith, A. D., Keller, M., Rennick, C. J., Heazlewood, B, R., & Softley, T.P., Coulomb crystal mass spectrometry in a digital ion trap.
Physical Review A, 91(3) (2015).


Calmet, X., & Keller, M., Cosmological evolution of fundamental constants: From theory to experiment. Modern Physics Letters A, 30(22) (2014).

Gardner, A., Sheridan, K., Groom, W., Seymour-Smith, N., & Keller, M., Precision spectroscopy technique for dipole-allowed transitions in laser-cooled ions. Applied Physics B, 117, 755-762 (2014).

Kajita, M., Gopakumar, G., Abe, M., Hada, M., & Keller, M., Test of mp/me changes using vibrational transitions in N2+.Physical Review A, 89(3) (2014).

Takahashi, H., Morphew, J., Oručević, F., Noguchi, A., Kassa, E., & Keller, M., Novel laser machining of optical fibers for long cavities with low birefringence. Optics Express, 22(25) 31317-31328 (2014).


Keller, M., Interfacing atoms and light - The smaller the stronger. Science (Perspective), 340(6137), 1175-1176 (2013).

Takahashi, H., Wilson, A., Riley-Watson, A., Orucevic, F., Seymour-Smith, N.,  Keller, M., & Lange, W., An integrated fiber trap for single-ion photonics. New Journal of Physics, 15 (2013).   


Brama, E., Mortensen, A., Keller, M., & Lange, W., Heating rates in a thin ion trap for microcavity experiments. Applied Physics B, 107, 945-954 (2012).

Sheridan, K., Seymour-Smith, N., Gardner, A., & Keller, M., All-optical broadband excitation of the motional state of trapped ions. The European Physical Journey, 66, 289 (2012).


Sheridan, K., & Keller., M., Weighing of trapped ion crystals and its applications. New Journal of Physics, 13 (2011).  

Sheridan, K., Lange, W., & Keller, M., All-optical ion generation for ion trap loading. Applied Physics B, 104, 755-761 (2011). 


Seymour-Smith, N., Blythe, P., Keller, M., & Lange, W., Fast scanning cavity offset lock for laser frequency drift stabilization. Review of Scientific Instruments, 81, 075109 (2010) . 


Keller, M., Lange, B., Hayasaka, K., Lange, W., & Walther, H., Stable long-term coupling of a single ion to a cavity mode. Journal of Modern Optics, 54(11), 1607-1617 (2007).


Keller, M., Lange, B., Hayasaka, K., Lange, W., & Walther, H., Long-term stability of continuous-wave emission from an ion-cavity system. The European Physical Journal, 32, 161-166 (2005).